From f282c8f525788e6f15331bb6c94471012a7e5346 Mon Sep 17 00:00:00 2001
From: Muxi Yan <mxyan@google.com>
Date: Wed, 30 Aug 2017 14:40:15 -0700
Subject: [PATCH 01/20] Surface call deadline to Objective C API

---
 src/objective-c/GRPCClient/GRPCCall.h         |  5 +++++
 src/objective-c/GRPCClient/GRPCCall.m         |  3 ++-
 .../GRPCClient/private/GRPCChannel.h          |  1 +
 .../GRPCClient/private/GRPCChannel.m          |  8 ++++++-
 src/objective-c/GRPCClient/private/GRPCHost.h |  1 +
 src/objective-c/GRPCClient/private/GRPCHost.m |  6 +++++-
 .../GRPCClient/private/GRPCWrappedCall.h      |  3 ++-
 .../GRPCClient/private/GRPCWrappedCall.m      | 10 ++++++---
 src/objective-c/tests/GRPCClientTests.m       | 21 +++++++++++++++++++
 9 files changed, 51 insertions(+), 7 deletions(-)

diff --git a/src/objective-c/GRPCClient/GRPCCall.h b/src/objective-c/GRPCClient/GRPCCall.h
index 4d90cfd3847..bcf4ae9cc7f 100644
--- a/src/objective-c/GRPCClient/GRPCCall.h
+++ b/src/objective-c/GRPCClient/GRPCCall.h
@@ -169,6 +169,11 @@ extern id const kGRPCTrailersKey;
  */
 @property (atomic, copy, readwrite) NSString *serverName;
 
+/**
+ * The deadline for the RPC call in milliseconds. If set to 0, the deadline will be infinity.
+ */
+@property UInt64 deadline;
+
 /**
  * The container of the request headers of an RPC conforms to this protocol, which is a subset of
  * NSMutableDictionary's interface. It will become a NSMutableDictionary later on.
diff --git a/src/objective-c/GRPCClient/GRPCCall.m b/src/objective-c/GRPCClient/GRPCCall.m
index 436c19e354a..0f8f93cdae8 100644
--- a/src/objective-c/GRPCClient/GRPCCall.m
+++ b/src/objective-c/GRPCClient/GRPCCall.m
@@ -423,7 +423,8 @@ static NSString * const kBearerPrefix = @"Bearer ";
 
   _wrappedCall = [[GRPCWrappedCall alloc] initWithHost:_host
                                             serverName:_serverName
-                                                  path:_path];
+                                                  path:_path
+                                              deadline:_deadline];
   NSAssert(_wrappedCall, @"Error allocating RPC objects. Low memory?");
 
   [self sendHeaders:_requestHeaders];
diff --git a/src/objective-c/GRPCClient/private/GRPCChannel.h b/src/objective-c/GRPCClient/private/GRPCChannel.h
index e2aa5bd036f..67d78c3a44c 100644
--- a/src/objective-c/GRPCClient/private/GRPCChannel.h
+++ b/src/objective-c/GRPCClient/private/GRPCChannel.h
@@ -63,5 +63,6 @@ struct grpc_channel_credentials;
 
 - (nullable grpc_call *)unmanagedCallWithPath:(nonnull NSString *)path
                                    serverName:(nonnull NSString *)serverName
+                                     deadline:(UInt64)deadline
                               completionQueue:(nonnull GRPCCompletionQueue *)queue;
 @end
diff --git a/src/objective-c/GRPCClient/private/GRPCChannel.m b/src/objective-c/GRPCClient/private/GRPCChannel.m
index 52dbc70b997..72dc961d099 100644
--- a/src/objective-c/GRPCClient/private/GRPCChannel.m
+++ b/src/objective-c/GRPCClient/private/GRPCChannel.m
@@ -182,18 +182,24 @@ static grpc_channel_args *BuildChannelArgs(NSDictionary *dictionary) {
 
 - (grpc_call *)unmanagedCallWithPath:(NSString *)path
                           serverName:(NSString *)serverName
+                            deadline:(UInt64)deadline
                      completionQueue:(GRPCCompletionQueue *)queue {
   grpc_slice host_slice;
   if (serverName) {
     host_slice = grpc_slice_from_copied_string(serverName.UTF8String);
   }
   grpc_slice path_slice = grpc_slice_from_copied_string(path.UTF8String);
+  gpr_timespec deadline_ms = deadline == 0 ?
+                                 gpr_inf_future(GPR_CLOCK_REALTIME) :
+                                 gpr_time_add(
+                                     gpr_now(GPR_CLOCK_MONOTONIC),
+                                     gpr_time_from_millis(deadline, GPR_TIMESPAN));
   grpc_call *call = grpc_channel_create_call(_unmanagedChannel,
                                              NULL, GRPC_PROPAGATE_DEFAULTS,
                                              queue.unmanagedQueue,
                                              path_slice,
                                              serverName ? &host_slice : NULL,
-                                             gpr_inf_future(GPR_CLOCK_REALTIME), NULL);
+                                             deadline_ms, NULL);
   if (serverName) {
     grpc_slice_unref(host_slice);
   }
diff --git a/src/objective-c/GRPCClient/private/GRPCHost.h b/src/objective-c/GRPCClient/private/GRPCHost.h
index 0c1d7152405..7513cd0b8d8 100644
--- a/src/objective-c/GRPCClient/private/GRPCHost.h
+++ b/src/objective-c/GRPCClient/private/GRPCHost.h
@@ -55,6 +55,7 @@ struct grpc_channel_credentials;
 /** Create a grpc_call object to the provided path on this host. */
 - (nullable struct grpc_call *)unmanagedCallWithPath:(NSString *)path
                                           serverName:(NSString *)serverName
+                                            deadline:(UInt64)deadline
                                      completionQueue:(GRPCCompletionQueue *)queue;
 
 // TODO: There's a race when a new RPC is coming through just as an existing one is getting
diff --git a/src/objective-c/GRPCClient/private/GRPCHost.m b/src/objective-c/GRPCClient/private/GRPCHost.m
index 23794c1fed2..b847637ac59 100644
--- a/src/objective-c/GRPCClient/private/GRPCHost.m
+++ b/src/objective-c/GRPCClient/private/GRPCHost.m
@@ -121,6 +121,7 @@ static GRPCConnectivityMonitor *connectivityMonitor = nil;
 
 - (nullable grpc_call *)unmanagedCallWithPath:(NSString *)path
                                    serverName:(NSString *)serverName
+                                     deadline:(UInt64)deadline
                               completionQueue:(GRPCCompletionQueue *)queue {
   GRPCChannel *channel;
   // This is racing -[GRPCHost disconnect].
@@ -130,7 +131,10 @@ static GRPCConnectivityMonitor *connectivityMonitor = nil;
     }
     channel = _channel;
   }
-  return [channel unmanagedCallWithPath:path serverName:serverName completionQueue:queue];
+  return [channel unmanagedCallWithPath:path
+                             serverName:serverName
+                               deadline:deadline
+                        completionQueue:queue];
 }
 
 - (BOOL)setTLSPEMRootCerts:(nullable NSString *)pemRootCerts
diff --git a/src/objective-c/GRPCClient/private/GRPCWrappedCall.h b/src/objective-c/GRPCClient/private/GRPCWrappedCall.h
index 64075591a37..1995f1d0b59 100644
--- a/src/objective-c/GRPCClient/private/GRPCWrappedCall.h
+++ b/src/objective-c/GRPCClient/private/GRPCWrappedCall.h
@@ -76,7 +76,8 @@
 
 - (instancetype)initWithHost:(NSString *)host
                   serverName:(NSString *)serverName
-                        path:(NSString *)path NS_DESIGNATED_INITIALIZER;
+                        path:(NSString *)path
+                    deadline:(UInt64)deadline NS_DESIGNATED_INITIALIZER;
 
 - (void)startBatchWithOperations:(NSArray *)ops errorHandler:(void(^)())errorHandler;
 
diff --git a/src/objective-c/GRPCClient/private/GRPCWrappedCall.m b/src/objective-c/GRPCClient/private/GRPCWrappedCall.m
index 87dc33af88b..b855a96bee5 100644
--- a/src/objective-c/GRPCClient/private/GRPCWrappedCall.m
+++ b/src/objective-c/GRPCClient/private/GRPCWrappedCall.m
@@ -238,12 +238,13 @@
 }
 
 - (instancetype)init {
-  return [self initWithHost:nil serverName:nil path:nil];
+  return [self initWithHost:nil serverName:nil path:nil deadline:0];
 }
 
 - (instancetype)initWithHost:(NSString *)host
                   serverName:(NSString *)serverName
-                        path:(NSString *)path {
+                        path:(NSString *)path
+                    deadline:(UInt64)deadline {
   if (!path || !host) {
     [NSException raise:NSInvalidArgumentException
                 format:@"path and host cannot be nil."];
@@ -255,7 +256,10 @@
     // queue. Currently we use a singleton queue.
     _queue = [GRPCCompletionQueue completionQueue];
 
-    _call = [[GRPCHost hostWithAddress:host] unmanagedCallWithPath:path serverName:serverName completionQueue:_queue];
+    _call = [[GRPCHost hostWithAddress:host] unmanagedCallWithPath:path
+                                                        serverName:serverName
+                                                          deadline:deadline
+                                                   completionQueue:_queue];
     if (_call == NULL) {
       return nil;
     }
diff --git a/src/objective-c/tests/GRPCClientTests.m b/src/objective-c/tests/GRPCClientTests.m
index 9afe5071217..d9c6932ea8b 100644
--- a/src/objective-c/tests/GRPCClientTests.m
+++ b/src/objective-c/tests/GRPCClientTests.m
@@ -422,4 +422,25 @@ static GRPCProtoMethod *kUnaryCallMethod;
   [self waitForExpectationsWithTimeout:TEST_TIMEOUT handler:nil];
 }
 
+- (void)testDeadline {
+  __weak XCTestExpectation *completion = [self expectationWithDescription:@"Empty RPC completed."];
+
+  GRPCCall *call = [[GRPCCall alloc] initWithHost:kHostAddress
+                                             path:kEmptyCallMethod.HTTPPath
+                                   requestsWriter:[GRXWriter writerWithValue:[NSData data]]];
+
+  id<GRXWriteable> responsesWriteable = [[GRXWriteable alloc] initWithValueHandler:^(NSData *value) {
+    XCTAssert(0, @"Failure: response received; Expect: no response received.");
+  } completionHandler:^(NSError *errorOrNil) {
+    XCTAssertNotNil(errorOrNil, @"Failure: no error received; Expect: receive deadline exceeded.");
+    XCTAssertEqual(errorOrNil.code, GRPCErrorCodeDeadlineExceeded);
+    [completion fulfill];
+  }];
+
+  call.deadline = 1;
+  [call startWithWriteable:responsesWriteable];
+
+  [self waitForExpectationsWithTimeout:TEST_TIMEOUT handler:nil];
+}
+
 @end

From c7c8e3cb1712438c64b1212911b6c22165982426 Mon Sep 17 00:00:00 2001
From: Muxi Yan <mxyan@google.com>
Date: Wed, 30 Aug 2017 15:36:47 -0700
Subject: [PATCH 02/20] Rename deadline to timeout

---
 src/objective-c/GRPCClient/GRPCCall.h                |  4 ++--
 src/objective-c/GRPCClient/GRPCCall.m                |  2 +-
 src/objective-c/GRPCClient/private/GRPCChannel.h     |  2 +-
 src/objective-c/GRPCClient/private/GRPCChannel.m     | 12 ++++++------
 src/objective-c/GRPCClient/private/GRPCHost.h        |  2 +-
 src/objective-c/GRPCClient/private/GRPCHost.m        |  4 ++--
 src/objective-c/GRPCClient/private/GRPCWrappedCall.h |  2 +-
 src/objective-c/GRPCClient/private/GRPCWrappedCall.m |  6 +++---
 src/objective-c/tests/GRPCClientTests.m              |  4 ++--
 9 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/src/objective-c/GRPCClient/GRPCCall.h b/src/objective-c/GRPCClient/GRPCCall.h
index bcf4ae9cc7f..26c920b973a 100644
--- a/src/objective-c/GRPCClient/GRPCCall.h
+++ b/src/objective-c/GRPCClient/GRPCCall.h
@@ -170,9 +170,9 @@ extern id const kGRPCTrailersKey;
 @property (atomic, copy, readwrite) NSString *serverName;
 
 /**
- * The deadline for the RPC call in milliseconds. If set to 0, the deadline will be infinity.
+ * The timeout for the RPC call in milliseconds. If set to 0, the call will not timeout.
  */
-@property UInt64 deadline;
+@property UInt64 timeout;
 
 /**
  * The container of the request headers of an RPC conforms to this protocol, which is a subset of
diff --git a/src/objective-c/GRPCClient/GRPCCall.m b/src/objective-c/GRPCClient/GRPCCall.m
index 0f8f93cdae8..d6c3a3c165a 100644
--- a/src/objective-c/GRPCClient/GRPCCall.m
+++ b/src/objective-c/GRPCClient/GRPCCall.m
@@ -424,7 +424,7 @@ static NSString * const kBearerPrefix = @"Bearer ";
   _wrappedCall = [[GRPCWrappedCall alloc] initWithHost:_host
                                             serverName:_serverName
                                                   path:_path
-                                              deadline:_deadline];
+                                               timeout:_timeout];
   NSAssert(_wrappedCall, @"Error allocating RPC objects. Low memory?");
 
   [self sendHeaders:_requestHeaders];
diff --git a/src/objective-c/GRPCClient/private/GRPCChannel.h b/src/objective-c/GRPCClient/private/GRPCChannel.h
index 67d78c3a44c..9dff86c271f 100644
--- a/src/objective-c/GRPCClient/private/GRPCChannel.h
+++ b/src/objective-c/GRPCClient/private/GRPCChannel.h
@@ -63,6 +63,6 @@ struct grpc_channel_credentials;
 
 - (nullable grpc_call *)unmanagedCallWithPath:(nonnull NSString *)path
                                    serverName:(nonnull NSString *)serverName
-                                     deadline:(UInt64)deadline
+                                      timeout:(UInt64)timeout
                               completionQueue:(nonnull GRPCCompletionQueue *)queue;
 @end
diff --git a/src/objective-c/GRPCClient/private/GRPCChannel.m b/src/objective-c/GRPCClient/private/GRPCChannel.m
index 72dc961d099..39b4e6c1a7e 100644
--- a/src/objective-c/GRPCClient/private/GRPCChannel.m
+++ b/src/objective-c/GRPCClient/private/GRPCChannel.m
@@ -182,18 +182,18 @@ static grpc_channel_args *BuildChannelArgs(NSDictionary *dictionary) {
 
 - (grpc_call *)unmanagedCallWithPath:(NSString *)path
                           serverName:(NSString *)serverName
-                            deadline:(UInt64)deadline
+                             timeout:(UInt64)timeout
                      completionQueue:(GRPCCompletionQueue *)queue {
   grpc_slice host_slice;
   if (serverName) {
     host_slice = grpc_slice_from_copied_string(serverName.UTF8String);
   }
   grpc_slice path_slice = grpc_slice_from_copied_string(path.UTF8String);
-  gpr_timespec deadline_ms = deadline == 0 ?
-                                 gpr_inf_future(GPR_CLOCK_REALTIME) :
-                                 gpr_time_add(
-                                     gpr_now(GPR_CLOCK_MONOTONIC),
-                                     gpr_time_from_millis(deadline, GPR_TIMESPAN));
+  gpr_timespec deadline_ms = timeout == 0 ?
+                                gpr_inf_future(GPR_CLOCK_REALTIME) :
+                                gpr_time_add(
+                                    gpr_now(GPR_CLOCK_MONOTONIC),
+                                    gpr_time_from_millis(timeout, GPR_TIMESPAN));
   grpc_call *call = grpc_channel_create_call(_unmanagedChannel,
                                              NULL, GRPC_PROPAGATE_DEFAULTS,
                                              queue.unmanagedQueue,
diff --git a/src/objective-c/GRPCClient/private/GRPCHost.h b/src/objective-c/GRPCClient/private/GRPCHost.h
index 7513cd0b8d8..a9b3032c9c6 100644
--- a/src/objective-c/GRPCClient/private/GRPCHost.h
+++ b/src/objective-c/GRPCClient/private/GRPCHost.h
@@ -55,7 +55,7 @@ struct grpc_channel_credentials;
 /** Create a grpc_call object to the provided path on this host. */
 - (nullable struct grpc_call *)unmanagedCallWithPath:(NSString *)path
                                           serverName:(NSString *)serverName
-                                            deadline:(UInt64)deadline
+                                             timeout:(UInt64)timeout
                                      completionQueue:(GRPCCompletionQueue *)queue;
 
 // TODO: There's a race when a new RPC is coming through just as an existing one is getting
diff --git a/src/objective-c/GRPCClient/private/GRPCHost.m b/src/objective-c/GRPCClient/private/GRPCHost.m
index b847637ac59..a0791827db3 100644
--- a/src/objective-c/GRPCClient/private/GRPCHost.m
+++ b/src/objective-c/GRPCClient/private/GRPCHost.m
@@ -121,7 +121,7 @@ static GRPCConnectivityMonitor *connectivityMonitor = nil;
 
 - (nullable grpc_call *)unmanagedCallWithPath:(NSString *)path
                                    serverName:(NSString *)serverName
-                                     deadline:(UInt64)deadline
+                                      timeout:(UInt64)timeout
                               completionQueue:(GRPCCompletionQueue *)queue {
   GRPCChannel *channel;
   // This is racing -[GRPCHost disconnect].
@@ -133,7 +133,7 @@ static GRPCConnectivityMonitor *connectivityMonitor = nil;
   }
   return [channel unmanagedCallWithPath:path
                              serverName:serverName
-                               deadline:deadline
+                                timeout:timeout
                         completionQueue:queue];
 }
 
diff --git a/src/objective-c/GRPCClient/private/GRPCWrappedCall.h b/src/objective-c/GRPCClient/private/GRPCWrappedCall.h
index 1995f1d0b59..c0a6c71c72f 100644
--- a/src/objective-c/GRPCClient/private/GRPCWrappedCall.h
+++ b/src/objective-c/GRPCClient/private/GRPCWrappedCall.h
@@ -77,7 +77,7 @@
 - (instancetype)initWithHost:(NSString *)host
                   serverName:(NSString *)serverName
                         path:(NSString *)path
-                    deadline:(UInt64)deadline NS_DESIGNATED_INITIALIZER;
+                     timeout:(UInt64)timeout NS_DESIGNATED_INITIALIZER;
 
 - (void)startBatchWithOperations:(NSArray *)ops errorHandler:(void(^)())errorHandler;
 
diff --git a/src/objective-c/GRPCClient/private/GRPCWrappedCall.m b/src/objective-c/GRPCClient/private/GRPCWrappedCall.m
index b855a96bee5..7366f319312 100644
--- a/src/objective-c/GRPCClient/private/GRPCWrappedCall.m
+++ b/src/objective-c/GRPCClient/private/GRPCWrappedCall.m
@@ -238,13 +238,13 @@
 }
 
 - (instancetype)init {
-  return [self initWithHost:nil serverName:nil path:nil deadline:0];
+  return [self initWithHost:nil serverName:nil path:nil timeout:0];
 }
 
 - (instancetype)initWithHost:(NSString *)host
                   serverName:(NSString *)serverName
                         path:(NSString *)path
-                    deadline:(UInt64)deadline {
+                     timeout:(UInt64)timeout {
   if (!path || !host) {
     [NSException raise:NSInvalidArgumentException
                 format:@"path and host cannot be nil."];
@@ -258,7 +258,7 @@
 
     _call = [[GRPCHost hostWithAddress:host] unmanagedCallWithPath:path
                                                         serverName:serverName
-                                                          deadline:deadline
+                                                           timeout:timeout
                                                    completionQueue:_queue];
     if (_call == NULL) {
       return nil;
diff --git a/src/objective-c/tests/GRPCClientTests.m b/src/objective-c/tests/GRPCClientTests.m
index d9c6932ea8b..d050319533a 100644
--- a/src/objective-c/tests/GRPCClientTests.m
+++ b/src/objective-c/tests/GRPCClientTests.m
@@ -422,7 +422,7 @@ static GRPCProtoMethod *kUnaryCallMethod;
   [self waitForExpectationsWithTimeout:TEST_TIMEOUT handler:nil];
 }
 
-- (void)testDeadline {
+- (void)testTimeout {
   __weak XCTestExpectation *completion = [self expectationWithDescription:@"Empty RPC completed."];
 
   GRPCCall *call = [[GRPCCall alloc] initWithHost:kHostAddress
@@ -437,7 +437,7 @@ static GRPCProtoMethod *kUnaryCallMethod;
     [completion fulfill];
   }];
 
-  call.deadline = 1;
+  call.timeout = 1;
   [call startWithWriteable:responsesWriteable];
 
   [self waitForExpectationsWithTimeout:TEST_TIMEOUT handler:nil];

From afa47005015295e65b932403142938f9bb9b72fc Mon Sep 17 00:00:00 2001
From: Muxi Yan <mxyan@google.com>
Date: Mon, 11 Sep 2017 12:22:49 -0700
Subject: [PATCH 03/20] Use Apple internal type for timeout

---
 src/objective-c/GRPCClient/GRPCCall.h                | 2 +-
 src/objective-c/GRPCClient/private/GRPCChannel.h     | 2 +-
 src/objective-c/GRPCClient/private/GRPCChannel.m     | 4 ++--
 src/objective-c/GRPCClient/private/GRPCHost.h        | 2 +-
 src/objective-c/GRPCClient/private/GRPCHost.m        | 2 +-
 src/objective-c/GRPCClient/private/GRPCWrappedCall.h | 2 +-
 src/objective-c/GRPCClient/private/GRPCWrappedCall.m | 2 +-
 7 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/objective-c/GRPCClient/GRPCCall.h b/src/objective-c/GRPCClient/GRPCCall.h
index 26c920b973a..03552779d87 100644
--- a/src/objective-c/GRPCClient/GRPCCall.h
+++ b/src/objective-c/GRPCClient/GRPCCall.h
@@ -172,7 +172,7 @@ extern id const kGRPCTrailersKey;
 /**
  * The timeout for the RPC call in milliseconds. If set to 0, the call will not timeout.
  */
-@property UInt64 timeout;
+@property NSTimeInterval timeout;
 
 /**
  * The container of the request headers of an RPC conforms to this protocol, which is a subset of
diff --git a/src/objective-c/GRPCClient/private/GRPCChannel.h b/src/objective-c/GRPCClient/private/GRPCChannel.h
index 9dff86c271f..d37182f754c 100644
--- a/src/objective-c/GRPCClient/private/GRPCChannel.h
+++ b/src/objective-c/GRPCClient/private/GRPCChannel.h
@@ -63,6 +63,6 @@ struct grpc_channel_credentials;
 
 - (nullable grpc_call *)unmanagedCallWithPath:(nonnull NSString *)path
                                    serverName:(nonnull NSString *)serverName
-                                      timeout:(UInt64)timeout
+                                      timeout:(NSTimeInterval)timeout
                               completionQueue:(nonnull GRPCCompletionQueue *)queue;
 @end
diff --git a/src/objective-c/GRPCClient/private/GRPCChannel.m b/src/objective-c/GRPCClient/private/GRPCChannel.m
index 39b4e6c1a7e..2eb02115504 100644
--- a/src/objective-c/GRPCClient/private/GRPCChannel.m
+++ b/src/objective-c/GRPCClient/private/GRPCChannel.m
@@ -182,7 +182,7 @@ static grpc_channel_args *BuildChannelArgs(NSDictionary *dictionary) {
 
 - (grpc_call *)unmanagedCallWithPath:(NSString *)path
                           serverName:(NSString *)serverName
-                             timeout:(UInt64)timeout
+                             timeout:(NSTimeInterval)timeout
                      completionQueue:(GRPCCompletionQueue *)queue {
   grpc_slice host_slice;
   if (serverName) {
@@ -193,7 +193,7 @@ static grpc_channel_args *BuildChannelArgs(NSDictionary *dictionary) {
                                 gpr_inf_future(GPR_CLOCK_REALTIME) :
                                 gpr_time_add(
                                     gpr_now(GPR_CLOCK_MONOTONIC),
-                                    gpr_time_from_millis(timeout, GPR_TIMESPAN));
+                                    gpr_time_from_millis((int64_t)(timeout * 1000), GPR_TIMESPAN));
   grpc_call *call = grpc_channel_create_call(_unmanagedChannel,
                                              NULL, GRPC_PROPAGATE_DEFAULTS,
                                              queue.unmanagedQueue,
diff --git a/src/objective-c/GRPCClient/private/GRPCHost.h b/src/objective-c/GRPCClient/private/GRPCHost.h
index a9b3032c9c6..58171211b0e 100644
--- a/src/objective-c/GRPCClient/private/GRPCHost.h
+++ b/src/objective-c/GRPCClient/private/GRPCHost.h
@@ -55,7 +55,7 @@ struct grpc_channel_credentials;
 /** Create a grpc_call object to the provided path on this host. */
 - (nullable struct grpc_call *)unmanagedCallWithPath:(NSString *)path
                                           serverName:(NSString *)serverName
-                                             timeout:(UInt64)timeout
+                                             timeout:(NSTimeInterval)timeout
                                      completionQueue:(GRPCCompletionQueue *)queue;
 
 // TODO: There's a race when a new RPC is coming through just as an existing one is getting
diff --git a/src/objective-c/GRPCClient/private/GRPCHost.m b/src/objective-c/GRPCClient/private/GRPCHost.m
index a0791827db3..f73e9cbc507 100644
--- a/src/objective-c/GRPCClient/private/GRPCHost.m
+++ b/src/objective-c/GRPCClient/private/GRPCHost.m
@@ -121,7 +121,7 @@ static GRPCConnectivityMonitor *connectivityMonitor = nil;
 
 - (nullable grpc_call *)unmanagedCallWithPath:(NSString *)path
                                    serverName:(NSString *)serverName
-                                      timeout:(UInt64)timeout
+                                      timeout:(NSTimeInterval)timeout
                               completionQueue:(GRPCCompletionQueue *)queue {
   GRPCChannel *channel;
   // This is racing -[GRPCHost disconnect].
diff --git a/src/objective-c/GRPCClient/private/GRPCWrappedCall.h b/src/objective-c/GRPCClient/private/GRPCWrappedCall.h
index c0a6c71c72f..1cd9da8f3ea 100644
--- a/src/objective-c/GRPCClient/private/GRPCWrappedCall.h
+++ b/src/objective-c/GRPCClient/private/GRPCWrappedCall.h
@@ -77,7 +77,7 @@
 - (instancetype)initWithHost:(NSString *)host
                   serverName:(NSString *)serverName
                         path:(NSString *)path
-                     timeout:(UInt64)timeout NS_DESIGNATED_INITIALIZER;
+                     timeout:(NSTimeInterval)timeout NS_DESIGNATED_INITIALIZER;
 
 - (void)startBatchWithOperations:(NSArray *)ops errorHandler:(void(^)())errorHandler;
 
diff --git a/src/objective-c/GRPCClient/private/GRPCWrappedCall.m b/src/objective-c/GRPCClient/private/GRPCWrappedCall.m
index 7366f319312..b0b1223b64c 100644
--- a/src/objective-c/GRPCClient/private/GRPCWrappedCall.m
+++ b/src/objective-c/GRPCClient/private/GRPCWrappedCall.m
@@ -244,7 +244,7 @@
 - (instancetype)initWithHost:(NSString *)host
                   serverName:(NSString *)serverName
                         path:(NSString *)path
-                     timeout:(UInt64)timeout {
+                     timeout:(NSTimeInterval)timeout {
   if (!path || !host) {
     [NSException raise:NSInvalidArgumentException
                 format:@"path and host cannot be nil."];

From f6e61bf7686bfce40d4f3912fd9eeb2ba6987e62 Mon Sep 17 00:00:00 2001
From: Muxi Yan <mxyan@google.com>
Date: Mon, 11 Sep 2017 15:48:51 -0700
Subject: [PATCH 04/20] Add comment for timeout; assert on negative timeout
 value; fix timeout test

---
 src/objective-c/GRPCClient/GRPCCall.h            | 4 +++-
 src/objective-c/GRPCClient/private/GRPCChannel.m | 4 ++++
 src/objective-c/tests/GRPCClientTests.m          | 2 +-
 3 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/objective-c/GRPCClient/GRPCCall.h b/src/objective-c/GRPCClient/GRPCCall.h
index 03552779d87..3b0ef56c3af 100644
--- a/src/objective-c/GRPCClient/GRPCCall.h
+++ b/src/objective-c/GRPCClient/GRPCCall.h
@@ -170,7 +170,9 @@ extern id const kGRPCTrailersKey;
 @property (atomic, copy, readwrite) NSString *serverName;
 
 /**
- * The timeout for the RPC call in milliseconds. If set to 0, the call will not timeout.
+ * The timeout for the RPC call in milliseconds. If set to 0, the call will not timeout. If set to
+ * positive, the gRPC call returns with status GRPCErrorCodeDeadlineExceeded. A negative value is
+ * not allowed.
  */
 @property NSTimeInterval timeout;
 
diff --git a/src/objective-c/GRPCClient/private/GRPCChannel.m b/src/objective-c/GRPCClient/private/GRPCChannel.m
index 2eb02115504..b78b14f2afd 100644
--- a/src/objective-c/GRPCClient/private/GRPCChannel.m
+++ b/src/objective-c/GRPCClient/private/GRPCChannel.m
@@ -184,6 +184,10 @@ static grpc_channel_args *BuildChannelArgs(NSDictionary *dictionary) {
                           serverName:(NSString *)serverName
                              timeout:(NSTimeInterval)timeout
                      completionQueue:(GRPCCompletionQueue *)queue {
+  GPR_ASSERT(timeout >= 0);
+  if (timeout < 0) {
+    timeout = 0;
+  }
   grpc_slice host_slice;
   if (serverName) {
     host_slice = grpc_slice_from_copied_string(serverName.UTF8String);
diff --git a/src/objective-c/tests/GRPCClientTests.m b/src/objective-c/tests/GRPCClientTests.m
index d050319533a..4be3d1c5e87 100644
--- a/src/objective-c/tests/GRPCClientTests.m
+++ b/src/objective-c/tests/GRPCClientTests.m
@@ -437,7 +437,7 @@ static GRPCProtoMethod *kUnaryCallMethod;
     [completion fulfill];
   }];
 
-  call.timeout = 1;
+  call.timeout = 0.001;
   [call startWithWriteable:responsesWriteable];
 
   [self waitForExpectationsWithTimeout:TEST_TIMEOUT handler:nil];

From 3c8f6dbffd715d0dd9ff03555b15a20c12c3f3ae Mon Sep 17 00:00:00 2001
From: Matt Kwong <mattkwong@google.com>
Date: Tue, 12 Sep 2017 13:19:49 -0700
Subject: [PATCH 05/20] Remove leftover instance of clear_alarms

---
 tools/run_tests/run_performance_tests.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/run_tests/run_performance_tests.py b/tools/run_tests/run_performance_tests.py
index 9b20fae78fd..6e407b4a410 100755
--- a/tools/run_tests/run_performance_tests.py
+++ b/tools/run_tests/run_performance_tests.py
@@ -556,7 +556,7 @@ def main():
         jobs = [scenario.jobspec]
         if scenario.workers:
           jobs.append(create_quit_jobspec(scenario.workers, remote_host=args.remote_driver_host))
-        scenario_failures, resultset = jobset.run(jobs, newline_on_success=True, maxjobs=1, clear_alarms=False)
+        scenario_failures, resultset = jobset.run(jobs, newline_on_success=True, maxjobs=1)
         total_scenario_failures += scenario_failures
         merged_resultset = dict(itertools.chain(six.iteritems(merged_resultset),
                                                 six.iteritems(resultset)))

From 69ce380ccc018a5618d35f5942f102c61b1e91f9 Mon Sep 17 00:00:00 2001
From: Matt Kwong <mattkwong@google.com>
Date: Tue, 12 Sep 2017 13:30:51 -0700
Subject: [PATCH 06/20] Revert "Merge pull request #12513 from
 grpc/revert-12289-sig_hand"

This reverts commit 81ad19d4be0e12d519b026a37982f14ff87a0847, reversing
changes made to ed63aac1952b8f19c7f1b4186cae139613c77603.
---
 tools/run_tests/python_utils/jobset.py   | 22 ++++++----------------
 tools/run_tests/run_performance_tests.py |  8 ++++----
 2 files changed, 10 insertions(+), 20 deletions(-)

diff --git a/tools/run_tests/python_utils/jobset.py b/tools/run_tests/python_utils/jobset.py
index 08d652ae3f3..6151a7276a9 100755
--- a/tools/run_tests/python_utils/jobset.py
+++ b/tools/run_tests/python_utils/jobset.py
@@ -71,10 +71,8 @@ def platform_string():
 if platform_string() == 'windows':
   pass
 else:
-  have_alarm = False
   def alarm_handler(unused_signum, unused_frame):
-    global have_alarm
-    have_alarm = False
+    pass
 
   signal.signal(signal.SIGCHLD, lambda unused_signum, unused_frame: None)
   signal.signal(signal.SIGALRM, alarm_handler)
@@ -367,10 +365,9 @@ class Jobset(object):
   """Manages one run of jobs."""
 
   def __init__(self, check_cancelled, maxjobs, newline_on_success, travis,
-               stop_on_failure, add_env, quiet_success, max_time, clear_alarms):
+               stop_on_failure, add_env, quiet_success, max_time):
     self._running = set()
     self._check_cancelled = check_cancelled
-    self._clear_alarms = clear_alarms
     self._cancelled = False
     self._failures = 0
     self._completed = 0
@@ -455,10 +452,7 @@ class Jobset(object):
       if platform_string() == 'windows':
         time.sleep(0.1)
       else:
-        global have_alarm
-        if not have_alarm:
-          have_alarm = True
-          signal.alarm(10)
+        signal.alarm(10)
         signal.pause()
 
   def cancelled(self):
@@ -474,10 +468,7 @@ class Jobset(object):
     while self._running:
       if self.cancelled(): pass  # poll cancellation
       self.reap()
-    # Clear the alarms when finished to avoid a race condition causing job
-    # failures. Don't do this when running multi-VM tests because clearing
-    # the alarms causes the test to stall
-    if platform_string() != 'windows' and self._clear_alarms:
+    if platform_string() != 'windows':
       signal.alarm(0)
     return not self.cancelled() and self._failures == 0
 
@@ -507,8 +498,7 @@ def run(cmdlines,
         add_env={},
         skip_jobs=False,
         quiet_success=False,
-        max_time=-1,
-        clear_alarms=True):
+        max_time=-1):
   if skip_jobs:
     resultset = {}
     skipped_job_result = JobResult()
@@ -520,7 +510,7 @@ def run(cmdlines,
   js = Jobset(check_cancelled,
               maxjobs if maxjobs is not None else _DEFAULT_MAX_JOBS,
               newline_on_success, travis, stop_on_failure, add_env,
-              quiet_success, max_time, clear_alarms)
+              quiet_success, max_time)
   for cmdline, remaining in tag_remaining(cmdlines):
     if not js.start(cmdline):
       break
diff --git a/tools/run_tests/run_performance_tests.py b/tools/run_tests/run_performance_tests.py
index 6e407b4a410..1bbab9e894f 100755
--- a/tools/run_tests/run_performance_tests.py
+++ b/tools/run_tests/run_performance_tests.py
@@ -183,7 +183,7 @@ def archive_repo(languages):
 
   jobset.message('START', 'Archiving local repository.', do_newline=True)
   num_failures, _ = jobset.run(
-      [archive_job], newline_on_success=True, maxjobs=1, clear_alarms=False)
+      [archive_job], newline_on_success=True, maxjobs=1)
   if num_failures == 0:
     jobset.message('SUCCESS',
                    'Archive with local repository created successfully.',
@@ -215,7 +215,7 @@ def prepare_remote_hosts(hosts, prepare_local=False):
             timeout_seconds=prepare_timeout))
   jobset.message('START', 'Preparing hosts.', do_newline=True)
   num_failures, _ = jobset.run(
-      prepare_jobs, newline_on_success=True, maxjobs=10, clear_alarms=False)
+      prepare_jobs, newline_on_success=True, maxjobs=10)
   if num_failures == 0:
     jobset.message('SUCCESS',
                    'Prepare step completed successfully.',
@@ -248,7 +248,7 @@ def build_on_remote_hosts(hosts, languages=scenario_config.LANGUAGES.keys(), bui
             timeout_seconds=build_timeout))
   jobset.message('START', 'Building.', do_newline=True)
   num_failures, _ = jobset.run(
-      build_jobs, newline_on_success=True, maxjobs=10, clear_alarms=False)
+      build_jobs, newline_on_success=True, maxjobs=10)
   if num_failures == 0:
     jobset.message('SUCCESS',
                    'Built successfully.',
@@ -414,7 +414,7 @@ def run_collect_perf_profile_jobs(hosts_and_base_names, scenario_name, flame_gra
     perf_report_jobs.append(perf_report_processor_job(host, perf_base_name, output_filename, flame_graph_reports))
 
   jobset.message('START', 'Collecting perf reports from qps workers', do_newline=True)
-  failures, _ = jobset.run(perf_report_jobs, newline_on_success=True, maxjobs=1, clear_alarms=False)
+  failures, _ = jobset.run(perf_report_jobs, newline_on_success=True, maxjobs=1)
   jobset.message('END', 'Collecting perf reports from qps workers', do_newline=True)
   return failures
 

From f68978c41f13197171325d944f971db7d9d85a54 Mon Sep 17 00:00:00 2001
From: jiangtaoli2016 <jiangtao@google.com>
Date: Thu, 14 Sep 2017 09:18:24 -0700
Subject: [PATCH 07/20] Pass exec_ctx in TSI zero_copy_protector create

---
 src/core/lib/security/transport/security_handshaker.c |  2 +-
 src/core/tsi/fake_transport_security.c                |  3 ++-
 src/core/tsi/transport_security.h                     | 10 ++++++++--
 src/core/tsi/transport_security_grpc.c                |  8 +++++---
 src/core/tsi/transport_security_grpc.h                |  3 ++-
 5 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/src/core/lib/security/transport/security_handshaker.c b/src/core/lib/security/transport/security_handshaker.c
index 975d5995232..3d196056177 100644
--- a/src/core/lib/security/transport/security_handshaker.c
+++ b/src/core/lib/security/transport/security_handshaker.c
@@ -137,7 +137,7 @@ static void on_peer_checked_inner(grpc_exec_ctx *exec_ctx,
   // Create zero-copy frame protector, if implemented.
   tsi_zero_copy_grpc_protector *zero_copy_protector = NULL;
   tsi_result result = tsi_handshaker_result_create_zero_copy_grpc_protector(
-      h->handshaker_result, NULL, &zero_copy_protector);
+      exec_ctx, h->handshaker_result, NULL, &zero_copy_protector);
   if (result != TSI_OK && result != TSI_UNIMPLEMENTED) {
     error = grpc_set_tsi_error_result(
         GRPC_ERROR_CREATE_FROM_STATIC_STRING(
diff --git a/src/core/tsi/fake_transport_security.c b/src/core/tsi/fake_transport_security.c
index e7b3be3d86f..64043fea088 100644
--- a/src/core/tsi/fake_transport_security.c
+++ b/src/core/tsi/fake_transport_security.c
@@ -493,7 +493,8 @@ static tsi_result fake_handshaker_result_extract_peer(
 }
 
 static tsi_result fake_handshaker_result_create_zero_copy_grpc_protector(
-    const tsi_handshaker_result *self, size_t *max_output_protected_frame_size,
+    void *exec_ctx, const tsi_handshaker_result *self,
+    size_t *max_output_protected_frame_size,
     tsi_zero_copy_grpc_protector **protector) {
   *protector =
       tsi_create_fake_zero_copy_grpc_protector(max_output_protected_frame_size);
diff --git a/src/core/tsi/transport_security.h b/src/core/tsi/transport_security.h
index b0d7039850d..3bba38149c8 100644
--- a/src/core/tsi/transport_security.h
+++ b/src/core/tsi/transport_security.h
@@ -84,11 +84,17 @@ struct tsi_handshaker {
 };
 
 /* Base for tsi_handshaker_result implementations.
-   See transport_security_interface.h for documentation. */
+   See transport_security_interface.h for documentation.
+   The exec_ctx parameter in create_zero_copy_grpc_protector is supposed to be
+   of type grpc_exec_ctx*, but we're using void* instead to avoid making the TSI
+   API depend on grpc. The create_zero_copy_grpc_protector() method is only used
+   in grpc, where we do need the exec_ctx passed through, but the API still
+   needs to compile in other applications, where grpc_exec_ctx is not defined.
+*/
 typedef struct {
   tsi_result (*extract_peer)(const tsi_handshaker_result *self, tsi_peer *peer);
   tsi_result (*create_zero_copy_grpc_protector)(
-      const tsi_handshaker_result *self,
+      void *exec_ctx, const tsi_handshaker_result *self,
       size_t *max_output_protected_frame_size,
       tsi_zero_copy_grpc_protector **protector);
   tsi_result (*create_frame_protector)(const tsi_handshaker_result *self,
diff --git a/src/core/tsi/transport_security_grpc.c b/src/core/tsi/transport_security_grpc.c
index 773b35e7179..affd995230e 100644
--- a/src/core/tsi/transport_security_grpc.c
+++ b/src/core/tsi/transport_security_grpc.c
@@ -20,16 +20,18 @@
 
 /* This method creates a tsi_zero_copy_grpc_protector object.  */
 tsi_result tsi_handshaker_result_create_zero_copy_grpc_protector(
-    const tsi_handshaker_result *self, size_t *max_output_protected_frame_size,
+    grpc_exec_ctx *exec_ctx, const tsi_handshaker_result *self,
+    size_t *max_output_protected_frame_size,
     tsi_zero_copy_grpc_protector **protector) {
-  if (self == NULL || self->vtable == NULL || protector == NULL) {
+  if (exec_ctx == NULL || self == NULL || self->vtable == NULL ||
+      protector == NULL) {
     return TSI_INVALID_ARGUMENT;
   }
   if (self->vtable->create_zero_copy_grpc_protector == NULL) {
     return TSI_UNIMPLEMENTED;
   }
   return self->vtable->create_zero_copy_grpc_protector(
-      self, max_output_protected_frame_size, protector);
+      exec_ctx, self, max_output_protected_frame_size, protector);
 }
 
 /* --- tsi_zero_copy_grpc_protector common implementation. ---
diff --git a/src/core/tsi/transport_security_grpc.h b/src/core/tsi/transport_security_grpc.h
index 375a758888b..ca6755c12fa 100644
--- a/src/core/tsi/transport_security_grpc.h
+++ b/src/core/tsi/transport_security_grpc.h
@@ -30,7 +30,8 @@ extern "C" {
    assuming there is no fatal error.
    The caller is responsible for destroying the protector.  */
 tsi_result tsi_handshaker_result_create_zero_copy_grpc_protector(
-    const tsi_handshaker_result *self, size_t *max_output_protected_frame_size,
+    grpc_exec_ctx *exec_ctx, const tsi_handshaker_result *self,
+    size_t *max_output_protected_frame_size,
     tsi_zero_copy_grpc_protector **protector);
 
 /* -- tsi_zero_copy_grpc_protector object --  */

From 27bf05d003f48e6f95b836a5e5450e4bb787f9ef Mon Sep 17 00:00:00 2001
From: Alexander Polcyn <apolcyn@google.com>
Date: Mon, 7 Aug 2017 18:09:11 -0700
Subject: [PATCH 08/20] Add tests for c-ares wrapper using a local DNS server.

---
 CMakeLists.txt                                | 184 ++++++++++
 Makefile                                      | 188 ++++++++++
 bazel/grpc_build_system.bzl                   |  16 +
 .../resolver/dns/c_ares/dns_resolver_ares.c   |   2 +-
 .../resolver_component_tests_defs.include     |  92 +++++
 ...esolver_component_tests_runner.sh.template |   4 +
 .../tools/dockerfile/apt_get_basic.include    |   1 +
 .../tools/dockerfile/python_deps.include      |   2 +-
 test/cpp/naming/BUILD                         |  49 +++
 test/cpp/naming/gen_build_yaml.py             |  99 ++++++
 .../generate_resolver_component_tests.bzl     |  64 ++++
 test/cpp/naming/resolver_component_test.cc    | 323 ++++++++++++++++++
 .../naming/resolver_component_tests_runner.sh | 173 ++++++++++
 ...resolver_component_tests_runner_invoker.cc | 189 ++++++++++
 .../naming/resolver_test_record_groups.yaml   | 155 +++++++++
 test/cpp/naming/test_dns_server.py            | 134 ++++++++
 tools/buildgen/generate_build_additions.sh    |   1 +
 .../grpc_interop_csharp/Dockerfile            |   3 +-
 .../interoptest/grpc_interop_cxx/Dockerfile   |   3 +-
 .../interoptest/grpc_interop_go/Dockerfile    |   2 +-
 .../interoptest/grpc_interop_go1.7/Dockerfile |   2 +-
 .../interoptest/grpc_interop_go1.8/Dockerfile |   2 +-
 .../interoptest/grpc_interop_http2/Dockerfile |   2 +-
 .../interoptest/grpc_interop_java/Dockerfile  |   2 +-
 .../grpc_interop_java_oracle8/Dockerfile      |   2 +-
 .../interoptest/grpc_interop_node/Dockerfile  |   3 +-
 .../interoptest/grpc_interop_php/Dockerfile   |   1 +
 .../grpc_interop_python/Dockerfile            |   3 +-
 .../interoptest/grpc_interop_ruby/Dockerfile  |   3 +-
 .../test/csharp_jessie_x64/Dockerfile         |   3 +-
 .../dockerfile/test/cxx_jessie_x64/Dockerfile |   3 +-
 .../dockerfile/test/cxx_jessie_x86/Dockerfile |   3 +-
 .../test/cxx_ubuntu1404_x64/Dockerfile        |   3 +-
 .../test/cxx_ubuntu1604_x64/Dockerfile        |   3 +-
 tools/dockerfile/test/fuzzer/Dockerfile       |   3 +-
 .../test/multilang_jessie_x64/Dockerfile      |   3 +-
 .../test/node_jessie_x64/Dockerfile           |   3 +-
 .../test/php7_jessie_x64/Dockerfile           |   2 +-
 .../dockerfile/test/php_jessie_x64/Dockerfile |   3 +-
 .../test/python_jessie_x64/Dockerfile         |   3 +-
 .../test/python_pyenv_x64/Dockerfile          |   3 +-
 .../test/ruby_jessie_x64/Dockerfile           |   3 +-
 tools/dockerfile/test/sanity/Dockerfile       |   3 +-
 .../helper_scripts/prepare_build_macos_rc     |   2 +-
 .../generated/sources_and_headers.json        |  80 +++++
 tools/run_tests/generated/tests.json          |  46 +++
 46 files changed, 1845 insertions(+), 28 deletions(-)
 create mode 100644 templates/test/cpp/naming/resolver_component_tests_defs.include
 create mode 100644 templates/test/cpp/naming/resolver_component_tests_runner.sh.template
 create mode 100644 test/cpp/naming/BUILD
 create mode 100755 test/cpp/naming/gen_build_yaml.py
 create mode 100755 test/cpp/naming/generate_resolver_component_tests.bzl
 create mode 100644 test/cpp/naming/resolver_component_test.cc
 create mode 100755 test/cpp/naming/resolver_component_tests_runner.sh
 create mode 100644 test/cpp/naming/resolver_component_tests_runner_invoker.cc
 create mode 100644 test/cpp/naming/resolver_test_record_groups.yaml
 create mode 100755 test/cpp/naming/test_dns_server.py

diff --git a/CMakeLists.txt b/CMakeLists.txt
index dd68016be86..1186e2b5038 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -760,6 +760,18 @@ add_dependencies(buildtests_cxx thread_stress_test)
 if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
 add_dependencies(buildtests_cxx writes_per_rpc_test)
 endif()
+if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
+add_dependencies(buildtests_cxx resolver_component_test_unsecure)
+endif()
+if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
+add_dependencies(buildtests_cxx resolver_component_test)
+endif()
+if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
+add_dependencies(buildtests_cxx resolver_component_tests_runner_invoker_unsecure)
+endif()
+if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
+add_dependencies(buildtests_cxx resolver_component_tests_runner_invoker)
+endif()
 
 add_custom_target(buildtests
   DEPENDS buildtests_c buildtests_cxx)
@@ -14113,6 +14125,178 @@ target_link_libraries(inproc_nosec_test
   gpr
 )
 
+endif (gRPC_BUILD_TESTS)
+if (gRPC_BUILD_TESTS)
+if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
+
+add_executable(resolver_component_test_unsecure
+  test/cpp/naming/resolver_component_test.cc
+  third_party/googletest/googletest/src/gtest-all.cc
+  third_party/googletest/googlemock/src/gmock-all.cc
+)
+
+
+target_include_directories(resolver_component_test_unsecure
+  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}
+  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/include
+  PRIVATE ${BORINGSSL_ROOT_DIR}/include
+  PRIVATE ${PROTOBUF_ROOT_DIR}/src
+  PRIVATE ${BENCHMARK_ROOT_DIR}/include
+  PRIVATE ${ZLIB_ROOT_DIR}
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/zlib
+  PRIVATE ${CARES_INCLUDE_DIR}
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/cares/cares
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/gflags/include
+  PRIVATE third_party/googletest/googletest/include
+  PRIVATE third_party/googletest/googletest
+  PRIVATE third_party/googletest/googlemock/include
+  PRIVATE third_party/googletest/googlemock
+  PRIVATE ${_gRPC_PROTO_GENS_DIR}
+)
+
+target_link_libraries(resolver_component_test_unsecure
+  ${_gRPC_PROTOBUF_LIBRARIES}
+  ${_gRPC_ALLTARGETS_LIBRARIES}
+  grpc++_test_util_unsecure
+  grpc_test_util_unsecure
+  gpr_test_util
+  grpc++_unsecure
+  grpc_unsecure
+  gpr
+  grpc++_test_config
+  ${_gRPC_GFLAGS_LIBRARIES}
+)
+
+endif()
+endif (gRPC_BUILD_TESTS)
+if (gRPC_BUILD_TESTS)
+if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
+
+add_executable(resolver_component_test
+  test/cpp/naming/resolver_component_test.cc
+  third_party/googletest/googletest/src/gtest-all.cc
+  third_party/googletest/googlemock/src/gmock-all.cc
+)
+
+
+target_include_directories(resolver_component_test
+  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}
+  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/include
+  PRIVATE ${BORINGSSL_ROOT_DIR}/include
+  PRIVATE ${PROTOBUF_ROOT_DIR}/src
+  PRIVATE ${BENCHMARK_ROOT_DIR}/include
+  PRIVATE ${ZLIB_ROOT_DIR}
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/zlib
+  PRIVATE ${CARES_INCLUDE_DIR}
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/cares/cares
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/gflags/include
+  PRIVATE third_party/googletest/googletest/include
+  PRIVATE third_party/googletest/googletest
+  PRIVATE third_party/googletest/googlemock/include
+  PRIVATE third_party/googletest/googlemock
+  PRIVATE ${_gRPC_PROTO_GENS_DIR}
+)
+
+target_link_libraries(resolver_component_test
+  ${_gRPC_PROTOBUF_LIBRARIES}
+  ${_gRPC_ALLTARGETS_LIBRARIES}
+  grpc++_test_util
+  grpc_test_util
+  gpr_test_util
+  grpc++
+  grpc
+  gpr
+  grpc++_test_config
+  ${_gRPC_GFLAGS_LIBRARIES}
+)
+
+endif()
+endif (gRPC_BUILD_TESTS)
+if (gRPC_BUILD_TESTS)
+if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
+
+add_executable(resolver_component_tests_runner_invoker_unsecure
+  test/cpp/naming/resolver_component_tests_runner_invoker.cc
+  third_party/googletest/googletest/src/gtest-all.cc
+  third_party/googletest/googlemock/src/gmock-all.cc
+)
+
+
+target_include_directories(resolver_component_tests_runner_invoker_unsecure
+  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}
+  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/include
+  PRIVATE ${BORINGSSL_ROOT_DIR}/include
+  PRIVATE ${PROTOBUF_ROOT_DIR}/src
+  PRIVATE ${BENCHMARK_ROOT_DIR}/include
+  PRIVATE ${ZLIB_ROOT_DIR}
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/zlib
+  PRIVATE ${CARES_INCLUDE_DIR}
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/cares/cares
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/gflags/include
+  PRIVATE third_party/googletest/googletest/include
+  PRIVATE third_party/googletest/googletest
+  PRIVATE third_party/googletest/googlemock/include
+  PRIVATE third_party/googletest/googlemock
+  PRIVATE ${_gRPC_PROTO_GENS_DIR}
+)
+
+target_link_libraries(resolver_component_tests_runner_invoker_unsecure
+  ${_gRPC_PROTOBUF_LIBRARIES}
+  ${_gRPC_ALLTARGETS_LIBRARIES}
+  grpc++_test_util
+  grpc_test_util
+  gpr_test_util
+  grpc++
+  grpc
+  gpr
+  grpc++_test_config
+  ${_gRPC_GFLAGS_LIBRARIES}
+)
+
+endif()
+endif (gRPC_BUILD_TESTS)
+if (gRPC_BUILD_TESTS)
+if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
+
+add_executable(resolver_component_tests_runner_invoker
+  test/cpp/naming/resolver_component_tests_runner_invoker.cc
+  third_party/googletest/googletest/src/gtest-all.cc
+  third_party/googletest/googlemock/src/gmock-all.cc
+)
+
+
+target_include_directories(resolver_component_tests_runner_invoker
+  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}
+  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/include
+  PRIVATE ${BORINGSSL_ROOT_DIR}/include
+  PRIVATE ${PROTOBUF_ROOT_DIR}/src
+  PRIVATE ${BENCHMARK_ROOT_DIR}/include
+  PRIVATE ${ZLIB_ROOT_DIR}
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/zlib
+  PRIVATE ${CARES_INCLUDE_DIR}
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/cares/cares
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/gflags/include
+  PRIVATE third_party/googletest/googletest/include
+  PRIVATE third_party/googletest/googletest
+  PRIVATE third_party/googletest/googlemock/include
+  PRIVATE third_party/googletest/googlemock
+  PRIVATE ${_gRPC_PROTO_GENS_DIR}
+)
+
+target_link_libraries(resolver_component_tests_runner_invoker
+  ${_gRPC_PROTOBUF_LIBRARIES}
+  ${_gRPC_ALLTARGETS_LIBRARIES}
+  grpc++_test_util
+  grpc_test_util
+  gpr_test_util
+  grpc++
+  grpc
+  gpr
+  grpc++_test_config
+  ${_gRPC_GFLAGS_LIBRARIES}
+)
+
+endif()
 endif (gRPC_BUILD_TESTS)
 if (gRPC_BUILD_TESTS)
 
diff --git a/Makefile b/Makefile
index 0c3648566a9..61d6cae6ab5 100644
--- a/Makefile
+++ b/Makefile
@@ -1266,6 +1266,10 @@ h2_sockpair+trace_nosec_test: $(BINDIR)/$(CONFIG)/h2_sockpair+trace_nosec_test
 h2_sockpair_1byte_nosec_test: $(BINDIR)/$(CONFIG)/h2_sockpair_1byte_nosec_test
 h2_uds_nosec_test: $(BINDIR)/$(CONFIG)/h2_uds_nosec_test
 inproc_nosec_test: $(BINDIR)/$(CONFIG)/inproc_nosec_test
+resolver_component_test_unsecure: $(BINDIR)/$(CONFIG)/resolver_component_test_unsecure
+resolver_component_test: $(BINDIR)/$(CONFIG)/resolver_component_test
+resolver_component_tests_runner_invoker_unsecure: $(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker_unsecure
+resolver_component_tests_runner_invoker: $(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker
 api_fuzzer_one_entry: $(BINDIR)/$(CONFIG)/api_fuzzer_one_entry
 client_fuzzer_one_entry: $(BINDIR)/$(CONFIG)/client_fuzzer_one_entry
 hpack_parser_fuzzer_test_one_entry: $(BINDIR)/$(CONFIG)/hpack_parser_fuzzer_test_one_entry
@@ -1652,6 +1656,10 @@ buildtests_cxx: privatelibs_cxx \
   $(BINDIR)/$(CONFIG)/boringssl_x509_test \
   $(BINDIR)/$(CONFIG)/boringssl_tab_test \
   $(BINDIR)/$(CONFIG)/boringssl_v3name_test \
+  $(BINDIR)/$(CONFIG)/resolver_component_test_unsecure \
+  $(BINDIR)/$(CONFIG)/resolver_component_test \
+  $(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker_unsecure \
+  $(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker \
 
 else
 buildtests_cxx: privatelibs_cxx \
@@ -1730,6 +1738,10 @@ buildtests_cxx: privatelibs_cxx \
   $(BINDIR)/$(CONFIG)/thread_manager_test \
   $(BINDIR)/$(CONFIG)/thread_stress_test \
   $(BINDIR)/$(CONFIG)/writes_per_rpc_test \
+  $(BINDIR)/$(CONFIG)/resolver_component_test_unsecure \
+  $(BINDIR)/$(CONFIG)/resolver_component_test \
+  $(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker_unsecure \
+  $(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker \
 
 endif
 
@@ -2141,6 +2153,10 @@ test_cxx: buildtests_cxx
 	$(Q) $(BINDIR)/$(CONFIG)/thread_stress_test || ( echo test thread_stress_test failed ; exit 1 )
 	$(E) "[RUN]     Testing writes_per_rpc_test"
 	$(Q) $(BINDIR)/$(CONFIG)/writes_per_rpc_test || ( echo test writes_per_rpc_test failed ; exit 1 )
+	$(E) "[RUN]     Testing resolver_component_tests_runner_invoker_unsecure"
+	$(Q) $(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker_unsecure || ( echo test resolver_component_tests_runner_invoker_unsecure failed ; exit 1 )
+	$(E) "[RUN]     Testing resolver_component_tests_runner_invoker"
+	$(Q) $(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker || ( echo test resolver_component_tests_runner_invoker failed ; exit 1 )
 
 
 flaky_test_cxx: buildtests_cxx
@@ -19480,6 +19496,178 @@ ifneq ($(NO_DEPS),true)
 endif
 
 
+RESOLVER_COMPONENT_TEST_UNSECURE_SRC = \
+    test/cpp/naming/resolver_component_test.cc \
+
+RESOLVER_COMPONENT_TEST_UNSECURE_OBJS = $(addprefix $(OBJDIR)/$(CONFIG)/, $(addsuffix .o, $(basename $(RESOLVER_COMPONENT_TEST_UNSECURE_SRC))))
+ifeq ($(NO_SECURE),true)
+
+# You can't build secure targets if you don't have OpenSSL.
+
+$(BINDIR)/$(CONFIG)/resolver_component_test_unsecure: openssl_dep_error
+
+else
+
+
+
+
+ifeq ($(NO_PROTOBUF),true)
+
+# You can't build the protoc plugins or protobuf-enabled targets if you don't have protobuf 3.0.0+.
+
+$(BINDIR)/$(CONFIG)/resolver_component_test_unsecure: protobuf_dep_error
+
+else
+
+$(BINDIR)/$(CONFIG)/resolver_component_test_unsecure: $(PROTOBUF_DEP) $(RESOLVER_COMPONENT_TEST_UNSECURE_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc++_test_util_unsecure.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util_unsecure.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++_unsecure.a $(LIBDIR)/$(CONFIG)/libgrpc_unsecure.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a
+	$(E) "[LD]      Linking $@"
+	$(Q) mkdir -p `dirname $@`
+	$(Q) $(LDXX) $(LDFLAGS) $(RESOLVER_COMPONENT_TEST_UNSECURE_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc++_test_util_unsecure.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util_unsecure.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++_unsecure.a $(LIBDIR)/$(CONFIG)/libgrpc_unsecure.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a $(LDLIBSXX) $(LDLIBS_PROTOBUF) $(LDLIBS) $(LDLIBS_SECURE) $(GTEST_LIB) -o $(BINDIR)/$(CONFIG)/resolver_component_test_unsecure
+
+endif
+
+endif
+
+$(OBJDIR)/$(CONFIG)/test/cpp/naming/resolver_component_test.o:  $(LIBDIR)/$(CONFIG)/libgrpc++_test_util_unsecure.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util_unsecure.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++_unsecure.a $(LIBDIR)/$(CONFIG)/libgrpc_unsecure.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a
+
+deps_resolver_component_test_unsecure: $(RESOLVER_COMPONENT_TEST_UNSECURE_OBJS:.o=.dep)
+
+ifneq ($(NO_SECURE),true)
+ifneq ($(NO_DEPS),true)
+-include $(RESOLVER_COMPONENT_TEST_UNSECURE_OBJS:.o=.dep)
+endif
+endif
+
+
+RESOLVER_COMPONENT_TEST_SRC = \
+    test/cpp/naming/resolver_component_test.cc \
+
+RESOLVER_COMPONENT_TEST_OBJS = $(addprefix $(OBJDIR)/$(CONFIG)/, $(addsuffix .o, $(basename $(RESOLVER_COMPONENT_TEST_SRC))))
+ifeq ($(NO_SECURE),true)
+
+# You can't build secure targets if you don't have OpenSSL.
+
+$(BINDIR)/$(CONFIG)/resolver_component_test: openssl_dep_error
+
+else
+
+
+
+
+ifeq ($(NO_PROTOBUF),true)
+
+# You can't build the protoc plugins or protobuf-enabled targets if you don't have protobuf 3.0.0+.
+
+$(BINDIR)/$(CONFIG)/resolver_component_test: protobuf_dep_error
+
+else
+
+$(BINDIR)/$(CONFIG)/resolver_component_test: $(PROTOBUF_DEP) $(RESOLVER_COMPONENT_TEST_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a
+	$(E) "[LD]      Linking $@"
+	$(Q) mkdir -p `dirname $@`
+	$(Q) $(LDXX) $(LDFLAGS) $(RESOLVER_COMPONENT_TEST_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a $(LDLIBSXX) $(LDLIBS_PROTOBUF) $(LDLIBS) $(LDLIBS_SECURE) $(GTEST_LIB) -o $(BINDIR)/$(CONFIG)/resolver_component_test
+
+endif
+
+endif
+
+$(OBJDIR)/$(CONFIG)/test/cpp/naming/resolver_component_test.o:  $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a
+
+deps_resolver_component_test: $(RESOLVER_COMPONENT_TEST_OBJS:.o=.dep)
+
+ifneq ($(NO_SECURE),true)
+ifneq ($(NO_DEPS),true)
+-include $(RESOLVER_COMPONENT_TEST_OBJS:.o=.dep)
+endif
+endif
+
+
+RESOLVER_COMPONENT_TESTS_RUNNER_INVOKER_UNSECURE_SRC = \
+    test/cpp/naming/resolver_component_tests_runner_invoker.cc \
+
+RESOLVER_COMPONENT_TESTS_RUNNER_INVOKER_UNSECURE_OBJS = $(addprefix $(OBJDIR)/$(CONFIG)/, $(addsuffix .o, $(basename $(RESOLVER_COMPONENT_TESTS_RUNNER_INVOKER_UNSECURE_SRC))))
+ifeq ($(NO_SECURE),true)
+
+# You can't build secure targets if you don't have OpenSSL.
+
+$(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker_unsecure: openssl_dep_error
+
+else
+
+
+
+
+ifeq ($(NO_PROTOBUF),true)
+
+# You can't build the protoc plugins or protobuf-enabled targets if you don't have protobuf 3.0.0+.
+
+$(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker_unsecure: protobuf_dep_error
+
+else
+
+$(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker_unsecure: $(PROTOBUF_DEP) $(RESOLVER_COMPONENT_TESTS_RUNNER_INVOKER_UNSECURE_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a
+	$(E) "[LD]      Linking $@"
+	$(Q) mkdir -p `dirname $@`
+	$(Q) $(LDXX) $(LDFLAGS) $(RESOLVER_COMPONENT_TESTS_RUNNER_INVOKER_UNSECURE_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a $(LDLIBSXX) $(LDLIBS_PROTOBUF) $(LDLIBS) $(LDLIBS_SECURE) $(GTEST_LIB) -o $(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker_unsecure
+
+endif
+
+endif
+
+$(OBJDIR)/$(CONFIG)/test/cpp/naming/resolver_component_tests_runner_invoker.o:  $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a
+
+deps_resolver_component_tests_runner_invoker_unsecure: $(RESOLVER_COMPONENT_TESTS_RUNNER_INVOKER_UNSECURE_OBJS:.o=.dep)
+
+ifneq ($(NO_SECURE),true)
+ifneq ($(NO_DEPS),true)
+-include $(RESOLVER_COMPONENT_TESTS_RUNNER_INVOKER_UNSECURE_OBJS:.o=.dep)
+endif
+endif
+
+
+RESOLVER_COMPONENT_TESTS_RUNNER_INVOKER_SRC = \
+    test/cpp/naming/resolver_component_tests_runner_invoker.cc \
+
+RESOLVER_COMPONENT_TESTS_RUNNER_INVOKER_OBJS = $(addprefix $(OBJDIR)/$(CONFIG)/, $(addsuffix .o, $(basename $(RESOLVER_COMPONENT_TESTS_RUNNER_INVOKER_SRC))))
+ifeq ($(NO_SECURE),true)
+
+# You can't build secure targets if you don't have OpenSSL.
+
+$(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker: openssl_dep_error
+
+else
+
+
+
+
+ifeq ($(NO_PROTOBUF),true)
+
+# You can't build the protoc plugins or protobuf-enabled targets if you don't have protobuf 3.0.0+.
+
+$(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker: protobuf_dep_error
+
+else
+
+$(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker: $(PROTOBUF_DEP) $(RESOLVER_COMPONENT_TESTS_RUNNER_INVOKER_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a
+	$(E) "[LD]      Linking $@"
+	$(Q) mkdir -p `dirname $@`
+	$(Q) $(LDXX) $(LDFLAGS) $(RESOLVER_COMPONENT_TESTS_RUNNER_INVOKER_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a $(LDLIBSXX) $(LDLIBS_PROTOBUF) $(LDLIBS) $(LDLIBS_SECURE) $(GTEST_LIB) -o $(BINDIR)/$(CONFIG)/resolver_component_tests_runner_invoker
+
+endif
+
+endif
+
+$(OBJDIR)/$(CONFIG)/test/cpp/naming/resolver_component_tests_runner_invoker.o:  $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a
+
+deps_resolver_component_tests_runner_invoker: $(RESOLVER_COMPONENT_TESTS_RUNNER_INVOKER_OBJS:.o=.dep)
+
+ifneq ($(NO_SECURE),true)
+ifneq ($(NO_DEPS),true)
+-include $(RESOLVER_COMPONENT_TESTS_RUNNER_INVOKER_OBJS:.o=.dep)
+endif
+endif
+
+
 API_FUZZER_ONE_ENTRY_SRC = \
     test/core/end2end/fuzzers/api_fuzzer.c \
     test/core/util/one_corpus_entry_fuzzer.c \
diff --git a/bazel/grpc_build_system.bzl b/bazel/grpc_build_system.bzl
index ba7ffcc9beb..6cfed6b0e72 100644
--- a/bazel/grpc_build_system.bzl
+++ b/bazel/grpc_build_system.bzl
@@ -106,6 +106,22 @@ def grpc_sh_test(name, srcs, args = [], data = []):
     args = args,
     data = data)
 
+def grpc_sh_binary(name, srcs, data = []):
+  native.sh_test(
+    name = name,
+    srcs = srcs,
+    data = data)
+
+def grpc_py_binary(name, srcs, data = [], deps = []):
+  if name == "test_dns_server":
+    # TODO: allow running test_dns_server in oss bazel test suite
+    deps = []
+  native.py_binary(
+    name = name,
+    srcs = srcs,
+    data = data,
+    deps = deps)
+
 def grpc_package(name, visibility = "private", features = []):
   if visibility == "tests":
     visibility = ["//test:__subpackages__"]
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.c b/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.c
index b87a3b70820..371c59b8cf3 100644
--- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.c
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.c
@@ -204,7 +204,7 @@ static char *choose_service_config(char *service_config_choice_json) {
         int random_pct = rand() % 100;
         int percentage;
         if (sscanf(field->value, "%d", &percentage) != 1 ||
-            random_pct > percentage) {
+            random_pct > percentage || percentage == 0) {
           service_config_json = NULL;
           break;
         }
diff --git a/templates/test/cpp/naming/resolver_component_tests_defs.include b/templates/test/cpp/naming/resolver_component_tests_defs.include
new file mode 100644
index 00000000000..6fa91c741ad
--- /dev/null
+++ b/templates/test/cpp/naming/resolver_component_tests_defs.include
@@ -0,0 +1,92 @@
+<%def name="resolver_component_tests(tests)">#!/bin/bash
+# Copyright 2015 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This file is auto-generated
+
+set -ex
+
+# all command args required in this set order
+FLAGS_test_bin_path=`echo "$1" | grep '\--test_bin_path=' | cut -d "=" -f 2`
+FLAGS_dns_server_bin_path=`echo "$2" | grep '\--dns_server_bin_path=' | cut -d "=" -f 2`
+FLAGS_records_config_path=`echo "$3" | grep '\--records_config_path=' | cut -d "=" -f 2`
+FLAGS_test_dns_server_port=`echo "$4" | grep '\--test_dns_server_port=' | cut -d "=" -f 2`
+
+for cmd_arg in "$FLAGS_test_bin_path" "$FLAGS_dns_server_bin_path" "$FLAGS_records_config_path" "$FLAGS_test_dns_server_port"; do
+  if [[ "$cmd_arg" == "" ]]; then
+    echo "Missing a CMD arg" && exit 1
+  fi
+done
+
+if [[ "$GRPC_DNS_RESOLVER" != "" && "$GRPC_DNS_RESOLVER" != ares ]]; then
+  echo "This test only works under GRPC_DNS_RESOLVER=ares. Have GRPC_DNS_RESOLVER=$GRPC_DNS_RESOLVER" && exit 1
+fi
+export GRPC_DNS_RESOLVER=ares
+
+"$FLAGS_dns_server_bin_path" --records_config_path="$FLAGS_records_config_path" --port="$FLAGS_test_dns_server_port" 2>&1 > /dev/null &
+DNS_SERVER_PID=$!
+echo "Local DNS server started. PID: $DNS_SERVER_PID"
+
+# Health check local DNS server TCP and UDP ports
+for ((i=0;i<30;i++));
+do
+  echo "Retry health-check DNS query to local DNS server over tcp and udp"
+  RETRY=0
+  dig A health-check-local-dns-server-is-alive.resolver-tests.grpctestingexp. @localhost -p "$FLAGS_test_dns_server_port" +tries=1 +timeout=1 | grep '123.123.123.123' || RETRY=1
+  dig A health-check-local-dns-server-is-alive.resolver-tests.grpctestingexp. @localhost -p "$FLAGS_test_dns_server_port" +tries=1 +timeout=1 +tcp | grep '123.123.123.123' || RETRY=1
+  if [[ "$RETRY" == 0 ]]; then
+    break
+  fi;
+  sleep 0.1
+done
+
+if [[ $RETRY == 1 ]]; then
+  echo "FAILED TO START LOCAL DNS SERVER"
+  kill -SIGTERM $DNS_SERVER_PID
+  wait
+  exit 1
+fi
+
+function terminate_all {
+  echo "Received signal. Terminating $! and $DNS_SERVER_PID"
+  kill -SIGTERM $! || true
+  kill -SIGTERM $DNS_SERVER_PID || true
+  wait
+  exit 1
+}
+
+trap terminate_all SIGTERM SIGINT
+
+EXIT_CODE=0
+# TODO: this test should check for GCE residency and skip tests using _grpclb._tcp.* SRV records once GCE residency checks are made
+# in the resolver.
+
+% for test in tests:
+$FLAGS_test_bin_path \\
+
+  --target_name='${test['target_name']}' \\
+
+  --expected_addrs='${test['expected_addrs']}' \\
+
+  --expected_chosen_service_config='${test['expected_chosen_service_config']}' \\
+
+  --expected_lb_policy='${test['expected_lb_policy']}' \\
+
+  --local_dns_server_address=127.0.0.1:$FLAGS_test_dns_server_port &
+wait $! || EXIT_CODE=1
+
+% endfor
+kill -SIGTERM $DNS_SERVER_PID || true
+wait
+exit $EXIT_CODE</%def>
diff --git a/templates/test/cpp/naming/resolver_component_tests_runner.sh.template b/templates/test/cpp/naming/resolver_component_tests_runner.sh.template
new file mode 100644
index 00000000000..86772dd1416
--- /dev/null
+++ b/templates/test/cpp/naming/resolver_component_tests_runner.sh.template
@@ -0,0 +1,4 @@
+%YAML 1.2
+--- |
+  <%namespace file="resolver_component_tests_defs.include" import="*"/>\
+  ${resolver_component_tests(resolver_component_test_cases)}
diff --git a/templates/tools/dockerfile/apt_get_basic.include b/templates/tools/dockerfile/apt_get_basic.include
index 9237e7dacef..6e19e65157a 100644
--- a/templates/tools/dockerfile/apt_get_basic.include
+++ b/templates/tools/dockerfile/apt_get_basic.include
@@ -6,6 +6,7 @@ RUN apt-get update && apt-get install -y ${'\\'}
   bzip2 ${'\\'}
   ccache ${'\\'}
   curl ${'\\'}
+  dnsutils ${'\\'}
   gcc ${'\\'}
   gcc-multilib ${'\\'}
   git ${'\\'}
diff --git a/templates/tools/dockerfile/python_deps.include b/templates/tools/dockerfile/python_deps.include
index 2c129814184..94b854ad212 100644
--- a/templates/tools/dockerfile/python_deps.include
+++ b/templates/tools/dockerfile/python_deps.include
@@ -11,4 +11,4 @@ RUN apt-get update && apt-get install -y ${'\\'}
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
diff --git a/test/cpp/naming/BUILD b/test/cpp/naming/BUILD
new file mode 100644
index 00000000000..24c3d1a4439
--- /dev/null
+++ b/test/cpp/naming/BUILD
@@ -0,0 +1,49 @@
+# Copyright 2017 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+package(
+    default_visibility = ["//visibility:public"],
+    features = [
+        "-layering_check",
+        "-parse_headers",
+    ],
+)
+
+licenses(["notice"])  # Apache v2
+
+load("//bazel:grpc_build_system.bzl", "grpc_sh_binary", "grpc_py_binary")
+
+load(":generate_resolver_component_tests.bzl", "generate_resolver_component_tests")
+
+# Meant to be invoked only through the top-level shell script driver.
+grpc_sh_binary(
+    name = "resolver_component_tests_runner",
+    srcs = [
+        "resolver_component_tests_runner.sh",
+    ],
+)
+
+grpc_py_binary(
+  name = "test_dns_server",
+  srcs = ["test_dns_server.py"],
+  data = [
+      "resolver_test_record_groups.yaml",
+  ],
+  deps = [
+      "twisted",
+      "yaml",
+  ]
+)
+
+generate_resolver_component_tests()
diff --git a/test/cpp/naming/gen_build_yaml.py b/test/cpp/naming/gen_build_yaml.py
new file mode 100755
index 00000000000..3a51fef7a0e
--- /dev/null
+++ b/test/cpp/naming/gen_build_yaml.py
@@ -0,0 +1,99 @@
+#!/usr/bin/env python2.7
+# Copyright 2015 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+"""Generates the appropriate build.json data for all the naming tests."""
+
+
+import yaml
+import collections
+import hashlib
+import json
+
+_LOCAL_DNS_SERVER_ADDRESS = '127.0.0.1:15353'
+
+def _append_zone_name(name, zone_name):
+  return '%s.%s' % (name, zone_name)
+
+def _build_expected_addrs_cmd_arg(expected_addrs):
+  out = []
+  for addr in expected_addrs:
+    out.append('%s,%s' % (addr['address'], str(addr['is_balancer'])))
+  return ';'.join(out)
+
+def main():
+  resolver_component_data = ''
+  with open('test/cpp/naming/resolver_test_record_groups.yaml') as f:
+    resolver_component_data = yaml.load(f)
+
+  json = {
+      'resolver_component_test_cases': [
+          {
+              'target_name': _append_zone_name(test_case['record_to_resolve'],
+                                                 resolver_component_data['resolver_component_tests_common_zone_name']),
+              'expected_addrs': _build_expected_addrs_cmd_arg(test_case['expected_addrs']),
+              'expected_chosen_service_config': (test_case['expected_chosen_service_config'] or ''),
+              'expected_lb_policy': (test_case['expected_lb_policy'] or ''),
+          } for test_case in resolver_component_data['resolver_component_tests']
+      ],
+      'targets': [
+          {
+              'name': 'resolver_component_test' + unsecure_build_config_suffix,
+              'build': 'test',
+              'language': 'c++',
+              'gtest': False,
+              'run': False,
+              'src': ['test/cpp/naming/resolver_component_test.cc'],
+              'platforms': ['linux', 'posix', 'mac'],
+              'deps': [
+                  'grpc++_test_util' + unsecure_build_config_suffix,
+                  'grpc_test_util' + unsecure_build_config_suffix,
+                  'gpr_test_util',
+                  'grpc++' + unsecure_build_config_suffix,
+                  'grpc' + unsecure_build_config_suffix,
+                  'gpr',
+                  'grpc++_test_config',
+              ],
+          } for unsecure_build_config_suffix in ['_unsecure', '']
+      ] + [
+          {
+              'name': 'resolver_component_tests_runner_invoker' + unsecure_build_config_suffix,
+              'build': 'test',
+              'language': 'c++',
+              'gtest': False,
+              'run': True,
+              'src': ['test/cpp/naming/resolver_component_tests_runner_invoker.cc'],
+              'platforms': ['linux', 'posix', 'mac'],
+              'deps': [
+                  'grpc++_test_util',
+                  'grpc_test_util',
+                  'gpr_test_util',
+                  'grpc++',
+                  'grpc',
+                  'gpr',
+                  'grpc++_test_config',
+              ],
+              'args': [
+                  '--test_bin_name=resolver_component_test%s' % unsecure_build_config_suffix,
+                  '--running_under_bazel=false',
+              ],
+          } for unsecure_build_config_suffix in ['_unsecure', '']
+      ]
+  }
+
+  print(yaml.dump(json))
+
+if __name__ == '__main__':
+  main()
diff --git a/test/cpp/naming/generate_resolver_component_tests.bzl b/test/cpp/naming/generate_resolver_component_tests.bzl
new file mode 100755
index 00000000000..118d9452d9f
--- /dev/null
+++ b/test/cpp/naming/generate_resolver_component_tests.bzl
@@ -0,0 +1,64 @@
+#!/usr/bin/env python2.7
+# Copyright 2015 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+load("//bazel:grpc_build_system.bzl", "grpc_sh_binary", "grpc_cc_test", "grpc_cc_binary")
+
+def generate_resolver_component_tests():
+  for unsecure_build_config_suffix in ['_unsecure', '']:
+    # meant to be invoked only through the top-level shell script driver
+    grpc_cc_binary(
+        name = "resolver_component_test%s" % unsecure_build_config_suffix,
+        testonly = 1,
+        srcs = [
+            "resolver_component_test.cc",
+        ],
+        external_deps = [
+            "gmock",
+        ],
+        deps = [
+            "//test/cpp/util:test_util%s" % unsecure_build_config_suffix,
+            "//test/core/util:grpc_test_util%s" % unsecure_build_config_suffix,
+            "//test/core/util:gpr_test_util",
+            "//:grpc++%s" % unsecure_build_config_suffix,
+            "//:grpc%s" % unsecure_build_config_suffix,
+            "//:gpr",
+            "//test/cpp/util:test_config",
+        ],
+    )
+    grpc_cc_test(
+        name = "resolver_component_tests_runner_invoker%s" % unsecure_build_config_suffix,
+        srcs = [
+            "resolver_component_tests_runner_invoker.cc",
+        ],
+        deps = [
+            "//test/cpp/util:test_util",
+            "//test/core/util:grpc_test_util",
+            "//test/core/util:gpr_test_util",
+            "//:grpc++",
+            "//:grpc",
+            "//:gpr",
+            "//test/cpp/util:test_config",
+        ],
+        data = [
+            ":resolver_component_tests_runner",
+            ":resolver_component_test%s" % unsecure_build_config_suffix,
+            ":test_dns_server",
+            "resolver_test_record_groups.yaml", # include the transitive dependency so that the dns sever py binary can locate this
+        ],
+        args = [
+            "--test_bin_name=resolver_component_test%s" % unsecure_build_config_suffix,
+            "--running_under_bazel=true",
+        ]
+    )
diff --git a/test/cpp/naming/resolver_component_test.cc b/test/cpp/naming/resolver_component_test.cc
new file mode 100644
index 00000000000..0857fb6a32c
--- /dev/null
+++ b/test/cpp/naming/resolver_component_test.cc
@@ -0,0 +1,323 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#include <grpc/grpc.h>
+#include <grpc/support/alloc.h>
+#include <grpc/support/host_port.h>
+#include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+#include <grpc/support/sync.h>
+#include <grpc/support/time.h>
+#include <string.h>
+
+#include <gflags/gflags.h>
+#include <gmock/gmock.h>
+#include <vector>
+
+#include "test/cpp/util/subprocess.h"
+#include "test/cpp/util/test_config.h"
+
+extern "C" {
+#include "src/core/ext/filters/client_channel/client_channel.h"
+#include "src/core/ext/filters/client_channel/resolver.h"
+#include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h"
+#include "src/core/ext/filters/client_channel/resolver_registry.h"
+#include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/iomgr/combiner.h"
+#include "src/core/lib/iomgr/executor.h"
+#include "src/core/lib/iomgr/iomgr.h"
+#include "src/core/lib/iomgr/resolve_address.h"
+#include "src/core/lib/iomgr/sockaddr_utils.h"
+#include "src/core/lib/support/env.h"
+#include "src/core/lib/support/string.h"
+#include "test/core/util/port.h"
+#include "test/core/util/test_config.h"
+}
+
+using std::vector;
+using grpc::SubProcess;
+using testing::UnorderedElementsAreArray;
+
+// Hack copied from "test/cpp/end2end/server_crash_test_client.cc"!
+// In some distros, gflags is in the namespace google, and in some others,
+// in gflags. This hack is enabling us to find both.
+namespace google {}
+namespace gflags {}
+using namespace google;
+using namespace gflags;
+
+DEFINE_string(target_name, "", "Target name to resolve.");
+DEFINE_string(expected_addrs, "",
+              "Comma-separated list of expected "
+              "'<ip0:port0>,<is_balancer0>;<ip1:port1>,<is_balancer1>;...' "
+              "addresses of "
+              "backend and/or balancers. 'is_balancer' should be bool, i.e. "
+              "true or false.");
+DEFINE_string(expected_chosen_service_config, "",
+              "Expected service config json string that gets chosen (no "
+              "whitespace). Empty for none.");
+DEFINE_string(
+    local_dns_server_address, "",
+    "Optional. This address is placed as the uri authority if present.");
+DEFINE_string(expected_lb_policy, "",
+              "Expected lb policy name that appears in resolver result channel "
+              "arg. Empty for none.");
+
+namespace {
+
+class GrpcLBAddress final {
+ public:
+  GrpcLBAddress(std::string address, bool is_balancer)
+      : is_balancer(is_balancer), address(address) {}
+
+  bool operator==(const GrpcLBAddress &other) const {
+    return this->is_balancer == other.is_balancer &&
+           this->address == other.address;
+  }
+
+  bool operator!=(const GrpcLBAddress &other) const {
+    return !(*this == other);
+  }
+
+  bool is_balancer;
+  std::string address;
+};
+
+vector<GrpcLBAddress> ParseExpectedAddrs(std::string expected_addrs) {
+  std::vector<GrpcLBAddress> out;
+  while (expected_addrs.size() != 0) {
+    // get the next <ip>,<port> (v4 or v6)
+    size_t next_comma = expected_addrs.find(",");
+    if (next_comma == std::string::npos) {
+      gpr_log(
+          GPR_ERROR,
+          "Missing ','. Expected_addrs arg should be a semi-colon-separated "
+          "list of "
+          "<ip-port>,<bool> pairs. Left-to-be-parsed arg is |%s|",
+          expected_addrs.c_str());
+      abort();
+    }
+    std::string next_addr = expected_addrs.substr(0, next_comma);
+    expected_addrs = expected_addrs.substr(next_comma + 1, std::string::npos);
+    // get the next is_balancer 'bool' associated with this address
+    size_t next_semicolon = expected_addrs.find(";");
+    bool is_balancer =
+        gpr_is_true(expected_addrs.substr(0, next_semicolon).c_str());
+    out.emplace_back(GrpcLBAddress(next_addr, is_balancer));
+    if (next_semicolon == std::string::npos) {
+      break;
+    }
+    expected_addrs =
+        expected_addrs.substr(next_semicolon + 1, std::string::npos);
+  }
+  if (out.size() == 0) {
+    gpr_log(GPR_ERROR,
+            "expected_addrs arg should be a comma-separated list of "
+            "<ip-port>,<bool> pairs");
+    abort();
+  }
+  return out;
+}
+
+gpr_timespec TestDeadline(void) {
+  return grpc_timeout_seconds_to_deadline(100);
+}
+
+struct ArgsStruct {
+  gpr_event ev;
+  gpr_atm done_atm;
+  gpr_mu *mu;
+  grpc_pollset *pollset;
+  grpc_pollset_set *pollset_set;
+  grpc_combiner *lock;
+  grpc_channel_args *channel_args;
+  vector<GrpcLBAddress> expected_addrs;
+  std::string expected_service_config_string;
+  std::string expected_lb_policy;
+};
+
+void ArgsInit(grpc_exec_ctx *exec_ctx, ArgsStruct *args) {
+  gpr_event_init(&args->ev);
+  args->pollset = (grpc_pollset *)gpr_zalloc(grpc_pollset_size());
+  grpc_pollset_init(args->pollset, &args->mu);
+  args->pollset_set = grpc_pollset_set_create();
+  grpc_pollset_set_add_pollset(exec_ctx, args->pollset_set, args->pollset);
+  args->lock = grpc_combiner_create();
+  gpr_atm_rel_store(&args->done_atm, 0);
+  args->channel_args = NULL;
+}
+
+void DoNothing(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {}
+
+void ArgsFinish(grpc_exec_ctx *exec_ctx, ArgsStruct *args) {
+  GPR_ASSERT(gpr_event_wait(&args->ev, TestDeadline()));
+  grpc_pollset_set_del_pollset(exec_ctx, args->pollset_set, args->pollset);
+  grpc_pollset_set_destroy(exec_ctx, args->pollset_set);
+  grpc_closure DoNothing_cb;
+  GRPC_CLOSURE_INIT(&DoNothing_cb, DoNothing, NULL, grpc_schedule_on_exec_ctx);
+  grpc_pollset_shutdown(exec_ctx, args->pollset, &DoNothing_cb);
+  // exec_ctx needs to be flushed before calling grpc_pollset_destroy()
+  grpc_channel_args_destroy(exec_ctx, args->channel_args);
+  grpc_exec_ctx_flush(exec_ctx);
+  grpc_pollset_destroy(exec_ctx, args->pollset);
+  gpr_free(args->pollset);
+  GRPC_COMBINER_UNREF(exec_ctx, args->lock, NULL);
+}
+
+gpr_timespec NSecondDeadline(int seconds) {
+  return gpr_time_add(gpr_now(GPR_CLOCK_REALTIME),
+                      gpr_time_from_seconds(seconds, GPR_TIMESPAN));
+}
+
+void PollPollsetUntilRequestDone(ArgsStruct *args) {
+  gpr_timespec deadline = NSecondDeadline(10);
+  while (true) {
+    bool done = gpr_atm_acq_load(&args->done_atm) != 0;
+    if (done) {
+      break;
+    }
+    gpr_timespec time_left =
+        gpr_time_sub(deadline, gpr_now(GPR_CLOCK_REALTIME));
+    gpr_log(GPR_DEBUG, "done=%d, time_left=%" PRId64 ".%09d", done,
+            time_left.tv_sec, time_left.tv_nsec);
+    GPR_ASSERT(gpr_time_cmp(time_left, gpr_time_0(GPR_TIMESPAN)) >= 0);
+    grpc_pollset_worker *worker = NULL;
+    grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+    gpr_mu_lock(args->mu);
+    GRPC_LOG_IF_ERROR(
+        "pollset_work",
+        grpc_pollset_work(&exec_ctx, args->pollset, &worker,
+                          gpr_now(GPR_CLOCK_REALTIME), NSecondDeadline(1)));
+    gpr_mu_unlock(args->mu);
+    grpc_exec_ctx_finish(&exec_ctx);
+  }
+  gpr_event_set(&args->ev, (void *)1);
+}
+
+void CheckServiceConfigResultLocked(grpc_channel_args *channel_args,
+                                    ArgsStruct *args) {
+  const grpc_arg *service_config_arg =
+      grpc_channel_args_find(channel_args, GRPC_ARG_SERVICE_CONFIG);
+  if (args->expected_service_config_string != "") {
+    GPR_ASSERT(service_config_arg != NULL);
+    GPR_ASSERT(service_config_arg->type == GRPC_ARG_STRING);
+    EXPECT_EQ(service_config_arg->value.string,
+              args->expected_service_config_string);
+  } else {
+    GPR_ASSERT(service_config_arg == NULL);
+  }
+}
+
+void CheckLBPolicyResultLocked(grpc_channel_args *channel_args,
+                               ArgsStruct *args) {
+  const grpc_arg *lb_policy_arg =
+      grpc_channel_args_find(channel_args, GRPC_ARG_LB_POLICY_NAME);
+  if (args->expected_lb_policy != "") {
+    GPR_ASSERT(lb_policy_arg != NULL);
+    GPR_ASSERT(lb_policy_arg->type == GRPC_ARG_STRING);
+    EXPECT_EQ(lb_policy_arg->value.string, args->expected_lb_policy);
+  } else {
+    GPR_ASSERT(lb_policy_arg == NULL);
+  }
+}
+
+void CheckResolverResultLocked(grpc_exec_ctx *exec_ctx, void *argsp,
+                               grpc_error *err) {
+  ArgsStruct *args = (ArgsStruct *)argsp;
+  grpc_channel_args *channel_args = args->channel_args;
+  const grpc_arg *channel_arg =
+      grpc_channel_args_find(channel_args, GRPC_ARG_LB_ADDRESSES);
+  GPR_ASSERT(channel_arg != NULL);
+  GPR_ASSERT(channel_arg->type == GRPC_ARG_POINTER);
+  grpc_lb_addresses *addresses =
+      (grpc_lb_addresses *)channel_arg->value.pointer.p;
+  gpr_log(GPR_INFO, "num addrs found: %" PRIdPTR ". expected %" PRIdPTR,
+          addresses->num_addresses, args->expected_addrs.size());
+  GPR_ASSERT(addresses->num_addresses == args->expected_addrs.size());
+  std::vector<GrpcLBAddress> found_lb_addrs;
+  for (size_t i = 0; i < addresses->num_addresses; i++) {
+    grpc_lb_address addr = addresses->addresses[i];
+    char *str;
+    grpc_sockaddr_to_string(&str, &addr.address, 1 /* normalize */);
+    gpr_log(GPR_INFO, "%s", str);
+    found_lb_addrs.emplace_back(
+        GrpcLBAddress(std::string(str), addr.is_balancer));
+    gpr_free(str);
+  }
+  if (args->expected_addrs.size() != found_lb_addrs.size()) {
+    gpr_log(GPR_DEBUG, "found lb addrs size is: %" PRIdPTR
+                       ". expected addrs size is %" PRIdPTR,
+            found_lb_addrs.size(), args->expected_addrs.size());
+    abort();
+  }
+  EXPECT_THAT(args->expected_addrs, UnorderedElementsAreArray(found_lb_addrs));
+  CheckServiceConfigResultLocked(channel_args, args);
+  CheckLBPolicyResultLocked(channel_args, args);
+  gpr_atm_rel_store(&args->done_atm, 1);
+  gpr_mu_lock(args->mu);
+  GRPC_LOG_IF_ERROR("pollset_kick", grpc_pollset_kick(args->pollset, NULL));
+  gpr_mu_unlock(args->mu);
+}
+
+TEST(ResolverComponentTest, TestResolvesRelevantRecords) {
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  ArgsStruct args;
+  ArgsInit(&exec_ctx, &args);
+  args.expected_addrs = ParseExpectedAddrs(FLAGS_expected_addrs);
+  args.expected_service_config_string = FLAGS_expected_chosen_service_config;
+  args.expected_lb_policy = FLAGS_expected_lb_policy;
+  // maybe build the address with an authority
+  char *whole_uri = NULL;
+  GPR_ASSERT(asprintf(&whole_uri, "dns://%s/%s",
+                      FLAGS_local_dns_server_address.c_str(),
+                      FLAGS_target_name.c_str()));
+  // create resolver and resolve
+  grpc_resolver *resolver = grpc_resolver_create(&exec_ctx, whole_uri, NULL,
+                                                 args.pollset_set, args.lock);
+  gpr_free(whole_uri);
+  grpc_closure on_resolver_result_changed;
+  GRPC_CLOSURE_INIT(&on_resolver_result_changed, CheckResolverResultLocked,
+                    (void *)&args, grpc_combiner_scheduler(args.lock));
+  grpc_resolver_next_locked(&exec_ctx, resolver, &args.channel_args,
+                            &on_resolver_result_changed);
+  grpc_exec_ctx_flush(&exec_ctx);
+  PollPollsetUntilRequestDone(&args);
+  GRPC_RESOLVER_UNREF(&exec_ctx, resolver, NULL);
+  ArgsFinish(&exec_ctx, &args);
+  grpc_exec_ctx_finish(&exec_ctx);
+}
+
+}  // namespace
+
+int main(int argc, char **argv) {
+  grpc_init();
+  grpc_test_init(argc, argv);
+  ::testing::InitGoogleTest(&argc, argv);
+  ParseCommandLineFlags(&argc, &argv, true);
+  if (FLAGS_target_name == "") {
+    gpr_log(GPR_ERROR, "Missing target_name param.");
+    abort();
+  }
+  if (FLAGS_local_dns_server_address != "") {
+    gpr_log(GPR_INFO, "Specifying authority in uris to: %s",
+            FLAGS_local_dns_server_address.c_str());
+  }
+  auto result = RUN_ALL_TESTS();
+  grpc_shutdown();
+  return result;
+}
diff --git a/test/cpp/naming/resolver_component_tests_runner.sh b/test/cpp/naming/resolver_component_tests_runner.sh
new file mode 100755
index 00000000000..83b03b67a30
--- /dev/null
+++ b/test/cpp/naming/resolver_component_tests_runner.sh
@@ -0,0 +1,173 @@
+#!/bin/bash
+# Copyright 2015 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This file is auto-generated
+
+set -ex
+
+# all command args required in this set order
+FLAGS_test_bin_path=`echo "$1" | grep '\--test_bin_path=' | cut -d "=" -f 2`
+FLAGS_dns_server_bin_path=`echo "$2" | grep '\--dns_server_bin_path=' | cut -d "=" -f 2`
+FLAGS_records_config_path=`echo "$3" | grep '\--records_config_path=' | cut -d "=" -f 2`
+FLAGS_test_dns_server_port=`echo "$4" | grep '\--test_dns_server_port=' | cut -d "=" -f 2`
+
+for cmd_arg in "$FLAGS_test_bin_path" "$FLAGS_dns_server_bin_path" "$FLAGS_records_config_path" "$FLAGS_test_dns_server_port"; do
+  if [[ "$cmd_arg" == "" ]]; then
+    echo "Missing a CMD arg" && exit 1
+  fi
+done
+
+if [[ "$GRPC_DNS_RESOLVER" != "" && "$GRPC_DNS_RESOLVER" != ares ]]; then
+  echo "This test only works under GRPC_DNS_RESOLVER=ares. Have GRPC_DNS_RESOLVER=$GRPC_DNS_RESOLVER" && exit 1
+fi
+export GRPC_DNS_RESOLVER=ares
+
+"$FLAGS_dns_server_bin_path" --records_config_path="$FLAGS_records_config_path" --port="$FLAGS_test_dns_server_port" 2>&1 > /dev/null &
+DNS_SERVER_PID=$!
+echo "Local DNS server started. PID: $DNS_SERVER_PID"
+
+# Health check local DNS server TCP and UDP ports
+for ((i=0;i<30;i++));
+do
+  echo "Retry health-check DNS query to local DNS server over tcp and udp"
+  RETRY=0
+  dig A health-check-local-dns-server-is-alive.resolver-tests.grpctestingexp. @localhost -p "$FLAGS_test_dns_server_port" +tries=1 +timeout=1 | grep '123.123.123.123' || RETRY=1
+  dig A health-check-local-dns-server-is-alive.resolver-tests.grpctestingexp. @localhost -p "$FLAGS_test_dns_server_port" +tries=1 +timeout=1 +tcp | grep '123.123.123.123' || RETRY=1
+  if [[ "$RETRY" == 0 ]]; then
+    break
+  fi;
+  sleep 0.1
+done
+
+if [[ $RETRY == 1 ]]; then
+  echo "FAILED TO START LOCAL DNS SERVER"
+  kill -SIGTERM $DNS_SERVER_PID
+  wait
+  exit 1
+fi
+
+function terminate_all {
+  echo "Received signal. Terminating $! and $DNS_SERVER_PID"
+  kill -SIGTERM $! || true
+  kill -SIGTERM $DNS_SERVER_PID || true
+  wait
+  exit 1
+}
+
+trap terminate_all SIGTERM SIGINT
+
+EXIT_CODE=0
+# TODO: this test should check for GCE residency and skip tests using _grpclb._tcp.* SRV records once GCE residency checks are made
+# in the resolver.
+
+$FLAGS_test_bin_path \
+  --target_name='srv-ipv4-single-target.resolver-tests.grpctestingexp.' \
+  --expected_addrs='1.2.3.4:1234,True' \
+  --expected_chosen_service_config='' \
+  --expected_lb_policy='' \
+  --local_dns_server_address=127.0.0.1:$FLAGS_test_dns_server_port &
+wait $! || EXIT_CODE=1
+
+$FLAGS_test_bin_path \
+  --target_name='srv-ipv4-multi-target.resolver-tests.grpctestingexp.' \
+  --expected_addrs='1.2.3.5:1234,True;1.2.3.6:1234,True;1.2.3.7:1234,True' \
+  --expected_chosen_service_config='' \
+  --expected_lb_policy='' \
+  --local_dns_server_address=127.0.0.1:$FLAGS_test_dns_server_port &
+wait $! || EXIT_CODE=1
+
+$FLAGS_test_bin_path \
+  --target_name='srv-ipv6-single-target.resolver-tests.grpctestingexp.' \
+  --expected_addrs='[2607:f8b0:400a:801::1001]:1234,True' \
+  --expected_chosen_service_config='' \
+  --expected_lb_policy='' \
+  --local_dns_server_address=127.0.0.1:$FLAGS_test_dns_server_port &
+wait $! || EXIT_CODE=1
+
+$FLAGS_test_bin_path \
+  --target_name='srv-ipv6-multi-target.resolver-tests.grpctestingexp.' \
+  --expected_addrs='[2607:f8b0:400a:801::1002]:1234,True;[2607:f8b0:400a:801::1003]:1234,True;[2607:f8b0:400a:801::1004]:1234,True' \
+  --expected_chosen_service_config='' \
+  --expected_lb_policy='' \
+  --local_dns_server_address=127.0.0.1:$FLAGS_test_dns_server_port &
+wait $! || EXIT_CODE=1
+
+$FLAGS_test_bin_path \
+  --target_name='srv-ipv4-simple-service-config.resolver-tests.grpctestingexp.' \
+  --expected_addrs='1.2.3.4:1234,True' \
+  --expected_chosen_service_config='{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"SimpleService","waitForReady":true}]}]}' \
+  --expected_lb_policy='round_robin' \
+  --local_dns_server_address=127.0.0.1:$FLAGS_test_dns_server_port &
+wait $! || EXIT_CODE=1
+
+$FLAGS_test_bin_path \
+  --target_name='ipv4-no-srv-simple-service-config.resolver-tests.grpctestingexp.' \
+  --expected_addrs='1.2.3.4:443,False' \
+  --expected_chosen_service_config='{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"NoSrvSimpleService","waitForReady":true}]}]}' \
+  --expected_lb_policy='round_robin' \
+  --local_dns_server_address=127.0.0.1:$FLAGS_test_dns_server_port &
+wait $! || EXIT_CODE=1
+
+$FLAGS_test_bin_path \
+  --target_name='ipv4-no-config-for-cpp.resolver-tests.grpctestingexp.' \
+  --expected_addrs='1.2.3.4:443,False' \
+  --expected_chosen_service_config='' \
+  --expected_lb_policy='' \
+  --local_dns_server_address=127.0.0.1:$FLAGS_test_dns_server_port &
+wait $! || EXIT_CODE=1
+
+$FLAGS_test_bin_path \
+  --target_name='ipv4-cpp-config-has-zero-percentage.resolver-tests.grpctestingexp.' \
+  --expected_addrs='1.2.3.4:443,False' \
+  --expected_chosen_service_config='' \
+  --expected_lb_policy='' \
+  --local_dns_server_address=127.0.0.1:$FLAGS_test_dns_server_port &
+wait $! || EXIT_CODE=1
+
+$FLAGS_test_bin_path \
+  --target_name='ipv4-second-language-is-cpp.resolver-tests.grpctestingexp.' \
+  --expected_addrs='1.2.3.4:443,False' \
+  --expected_chosen_service_config='{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"CppService","waitForReady":true}]}]}' \
+  --expected_lb_policy='round_robin' \
+  --local_dns_server_address=127.0.0.1:$FLAGS_test_dns_server_port &
+wait $! || EXIT_CODE=1
+
+$FLAGS_test_bin_path \
+  --target_name='ipv4-config-with-percentages.resolver-tests.grpctestingexp.' \
+  --expected_addrs='1.2.3.4:443,False' \
+  --expected_chosen_service_config='{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"AlwaysPickedService","waitForReady":true}]}]}' \
+  --expected_lb_policy='round_robin' \
+  --local_dns_server_address=127.0.0.1:$FLAGS_test_dns_server_port &
+wait $! || EXIT_CODE=1
+
+$FLAGS_test_bin_path \
+  --target_name='srv-ipv4-target-has-backend-and-balancer.resolver-tests.grpctestingexp.' \
+  --expected_addrs='1.2.3.4:1234,True;1.2.3.4:443,False' \
+  --expected_chosen_service_config='' \
+  --expected_lb_policy='' \
+  --local_dns_server_address=127.0.0.1:$FLAGS_test_dns_server_port &
+wait $! || EXIT_CODE=1
+
+$FLAGS_test_bin_path \
+  --target_name='srv-ipv6-target-has-backend-and-balancer.resolver-tests.grpctestingexp.' \
+  --expected_addrs='[2607:f8b0:400a:801::1002]:1234,True;[2607:f8b0:400a:801::1002]:443,False' \
+  --expected_chosen_service_config='' \
+  --expected_lb_policy='' \
+  --local_dns_server_address=127.0.0.1:$FLAGS_test_dns_server_port &
+wait $! || EXIT_CODE=1
+
+kill -SIGTERM $DNS_SERVER_PID || true
+wait
+exit $EXIT_CODE
diff --git a/test/cpp/naming/resolver_component_tests_runner_invoker.cc b/test/cpp/naming/resolver_component_tests_runner_invoker.cc
new file mode 100644
index 00000000000..b14391284d5
--- /dev/null
+++ b/test/cpp/naming/resolver_component_tests_runner_invoker.cc
@@ -0,0 +1,189 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#include <grpc/grpc.h>
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+#include <signal.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <gflags/gflags.h>
+#include <string>
+#include <thread>
+#include <vector>
+
+#include "test/cpp/util/subprocess.h"
+#include "test/cpp/util/test_config.h"
+
+extern "C" {
+#include "src/core/lib/support/env.h"
+#include "test/core/util/port.h"
+}
+
+DEFINE_bool(
+    running_under_bazel, false,
+    "True if this test is running under bazel. "
+    "False indicates that this test is running under run_tests.py. "
+    "Child process test binaries are located differently based on this flag. ");
+
+DEFINE_string(test_bin_name, "",
+              "Name, without the preceding path, of the test binary");
+
+DEFINE_string(grpc_test_directory_relative_to_test_srcdir, "/__main__",
+              "This flag only applies if runner_under_bazel is true. This "
+              "flag is ignored if runner_under_bazel is false. "
+              "Directory of the <repo-root>/test directory relative to bazel's "
+              "TEST_SRCDIR environment variable");
+
+using grpc::SubProcess;
+
+static volatile sig_atomic_t abort_wait_for_child = 0;
+
+static void sighandler(int sig) { abort_wait_for_child = 1; }
+
+static void register_sighandler() {
+  struct sigaction act;
+  memset(&act, 0, sizeof(act));
+  act.sa_handler = sighandler;
+  sigaction(SIGINT, &act, NULL);
+  sigaction(SIGTERM, &act, NULL);
+}
+
+namespace {
+
+const int kTestTimeoutSeconds = 60 * 2;
+
+void RunSigHandlingThread(SubProcess *test_driver, gpr_mu *test_driver_mu,
+                          gpr_cv *test_driver_cv, int *test_driver_done) {
+  gpr_timespec overall_deadline =
+      gpr_time_add(gpr_now(GPR_CLOCK_MONOTONIC),
+                   gpr_time_from_seconds(kTestTimeoutSeconds, GPR_TIMESPAN));
+  while (true) {
+    gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC);
+    if (gpr_time_cmp(now, overall_deadline) > 0 || abort_wait_for_child) break;
+    gpr_mu_lock(test_driver_mu);
+    if (*test_driver_done) {
+      gpr_mu_unlock(test_driver_mu);
+      return;
+    }
+    gpr_timespec wait_deadline = gpr_time_add(
+        gpr_now(GPR_CLOCK_MONOTONIC), gpr_time_from_seconds(1, GPR_TIMESPAN));
+    gpr_cv_wait(test_driver_cv, test_driver_mu, wait_deadline);
+    gpr_mu_unlock(test_driver_mu);
+  }
+  gpr_log(GPR_DEBUG,
+          "Test timeout reached or received signal. Interrupting test driver "
+          "child process.");
+  test_driver->Interrupt();
+  return;
+}
+}
+
+namespace grpc {
+
+namespace testing {
+
+void InvokeResolverComponentTestsRunner(std::string test_runner_bin_path,
+                                        std::string test_bin_path,
+                                        std::string dns_server_bin_path,
+                                        std::string records_config_path) {
+  int test_dns_server_port = grpc_pick_unused_port_or_die();
+
+  SubProcess *test_driver = new SubProcess(
+      {test_runner_bin_path, "--test_bin_path=" + test_bin_path,
+       "--dns_server_bin_path=" + dns_server_bin_path,
+       "--records_config_path=" + records_config_path,
+       "--test_dns_server_port=" + std::to_string(test_dns_server_port)});
+  gpr_mu test_driver_mu;
+  gpr_mu_init(&test_driver_mu);
+  gpr_cv test_driver_cv;
+  gpr_cv_init(&test_driver_cv);
+  int test_driver_done = 0;
+  register_sighandler();
+  std::thread sig_handling_thread(RunSigHandlingThread, test_driver,
+                                  &test_driver_mu, &test_driver_cv,
+                                  &test_driver_done);
+  int status = test_driver->Join();
+  if (WIFEXITED(status)) {
+    if (WEXITSTATUS(status)) {
+      gpr_log(GPR_INFO,
+              "Resolver component test test-runner exited with code %d",
+              WEXITSTATUS(status));
+      abort();
+    }
+  } else if (WIFSIGNALED(status)) {
+    gpr_log(GPR_INFO,
+            "Resolver component test test-runner ended from signal %d",
+            WTERMSIG(status));
+    abort();
+  } else {
+    gpr_log(GPR_INFO,
+            "Resolver component test test-runner ended with unknown status %d",
+            status);
+    abort();
+  }
+  gpr_mu_lock(&test_driver_mu);
+  test_driver_done = 1;
+  gpr_cv_signal(&test_driver_cv);
+  gpr_mu_unlock(&test_driver_mu);
+  sig_handling_thread.join();
+  delete test_driver;
+  gpr_mu_destroy(&test_driver_mu);
+  gpr_cv_destroy(&test_driver_cv);
+}
+
+}  // namespace testing
+
+}  // namespace grpc
+
+int main(int argc, char **argv) {
+  grpc::testing::InitTest(&argc, &argv, true);
+  grpc_init();
+  GPR_ASSERT(FLAGS_test_bin_name != "");
+  std::string my_bin = argv[0];
+  if (FLAGS_running_under_bazel) {
+    GPR_ASSERT(FLAGS_grpc_test_directory_relative_to_test_srcdir != "");
+    // Use bazel's TEST_SRCDIR environment variable to locate the "test data"
+    // binaries.
+    std::string const bin_dir =
+        gpr_getenv("TEST_SRCDIR") +
+        FLAGS_grpc_test_directory_relative_to_test_srcdir +
+        std::string("/test/cpp/naming");
+    // Invoke bazel's executeable links to the .sh and .py scripts (don't use
+    // the .sh and .py suffixes) to make
+    // sure that we're using bazel's test environment.
+    grpc::testing::InvokeResolverComponentTestsRunner(
+        bin_dir + "/resolver_component_tests_runner",
+        bin_dir + "/" + FLAGS_test_bin_name, bin_dir + "/test_dns_server",
+        bin_dir + "/resolver_test_record_groups.yaml");
+  } else {
+    // Get the current binary's directory relative to repo root to invoke the
+    // correct build config (asan/tsan/dbg, etc.).
+    std::string const bin_dir = my_bin.substr(0, my_bin.rfind('/'));
+    // Invoke the .sh and .py scripts directly where they are in source code.
+    grpc::testing::InvokeResolverComponentTestsRunner(
+        "test/cpp/naming/resolver_component_tests_runner.sh",
+        bin_dir + "/" + FLAGS_test_bin_name,
+        "test/cpp/naming/test_dns_server.py",
+        "test/cpp/naming/resolver_test_record_groups.yaml");
+  }
+  grpc_shutdown();
+  return 0;
+}
diff --git a/test/cpp/naming/resolver_test_record_groups.yaml b/test/cpp/naming/resolver_test_record_groups.yaml
new file mode 100644
index 00000000000..67c611d831f
--- /dev/null
+++ b/test/cpp/naming/resolver_test_record_groups.yaml
@@ -0,0 +1,155 @@
+resolver_component_tests_common_zone_name: resolver-tests.grpctestingexp.
+resolver_component_tests:
+- expected_addrs:
+  - {address: '1.2.3.4:1234', is_balancer: true}
+  expected_chosen_service_config: null
+  expected_lb_policy: null
+  record_to_resolve: srv-ipv4-single-target
+  records:
+    _grpclb._tcp.srv-ipv4-single-target:
+    - {TTL: '2100', data: 0 0 1234 ipv4-single-target, type: SRV}
+    ipv4-single-target:
+    - {TTL: '2100', data: 1.2.3.4, type: A}
+- expected_addrs:
+  - {address: '1.2.3.5:1234', is_balancer: true}
+  - {address: '1.2.3.6:1234', is_balancer: true}
+  - {address: '1.2.3.7:1234', is_balancer: true}
+  expected_chosen_service_config: null
+  expected_lb_policy: null
+  record_to_resolve: srv-ipv4-multi-target
+  records:
+    _grpclb._tcp.srv-ipv4-multi-target:
+    - {TTL: '2100', data: 0 0 1234 ipv4-multi-target, type: SRV}
+    ipv4-multi-target:
+    - {TTL: '2100', data: 1.2.3.5, type: A}
+    - {TTL: '2100', data: 1.2.3.6, type: A}
+    - {TTL: '2100', data: 1.2.3.7, type: A}
+- expected_addrs:
+  - {address: '[2607:f8b0:400a:801::1001]:1234', is_balancer: true}
+  expected_chosen_service_config: null
+  expected_lb_policy: null
+  record_to_resolve: srv-ipv6-single-target
+  records:
+    _grpclb._tcp.srv-ipv6-single-target:
+    - {TTL: '2100', data: 0 0 1234 ipv6-single-target, type: SRV}
+    ipv6-single-target:
+    - {TTL: '2100', data: '2607:f8b0:400a:801::1001', type: AAAA}
+- expected_addrs:
+  - {address: '[2607:f8b0:400a:801::1002]:1234', is_balancer: true}
+  - {address: '[2607:f8b0:400a:801::1003]:1234', is_balancer: true}
+  - {address: '[2607:f8b0:400a:801::1004]:1234', is_balancer: true}
+  expected_chosen_service_config: null
+  expected_lb_policy: null
+  record_to_resolve: srv-ipv6-multi-target
+  records:
+    _grpclb._tcp.srv-ipv6-multi-target:
+    - {TTL: '2100', data: 0 0 1234 ipv6-multi-target, type: SRV}
+    ipv6-multi-target:
+    - {TTL: '2100', data: '2607:f8b0:400a:801::1002', type: AAAA}
+    - {TTL: '2100', data: '2607:f8b0:400a:801::1003', type: AAAA}
+    - {TTL: '2100', data: '2607:f8b0:400a:801::1004', type: AAAA}
+- expected_addrs:
+  - {address: '1.2.3.4:1234', is_balancer: true}
+  expected_chosen_service_config: '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"SimpleService","waitForReady":true}]}]}'
+  expected_lb_policy: round_robin
+  record_to_resolve: srv-ipv4-simple-service-config
+  records:
+    _grpclb._tcp.srv-ipv4-simple-service-config:
+    - {TTL: '2100', data: 0 0 1234 ipv4-simple-service-config, type: SRV}
+    ipv4-simple-service-config:
+    - {TTL: '2100', data: 1.2.3.4, type: A}
+    srv-ipv4-simple-service-config:
+    - {TTL: '2100', data: 'grpc_config=[{"serviceConfig":{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"SimpleService","waitForReady":true}]}]}}]',
+      type: TXT}
+- expected_addrs:
+  - {address: '1.2.3.4:443', is_balancer: false}
+  expected_chosen_service_config: '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"NoSrvSimpleService","waitForReady":true}]}]}'
+  expected_lb_policy: round_robin
+  record_to_resolve: ipv4-no-srv-simple-service-config
+  records:
+    ipv4-no-srv-simple-service-config:
+    - {TTL: '2100', data: 1.2.3.4, type: A}
+    - {TTL: '2100', data: 'grpc_config=[{"serviceConfig":{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"NoSrvSimpleService","waitForReady":true}]}]}}]',
+      type: TXT}
+- expected_addrs:
+  - {address: '1.2.3.4:443', is_balancer: false}
+  expected_chosen_service_config: null
+  expected_lb_policy: null
+  record_to_resolve: ipv4-no-config-for-cpp
+  records:
+    ipv4-no-config-for-cpp:
+    - {TTL: '2100', data: 1.2.3.4, type: A}
+    - {TTL: '2100', data: 'grpc_config=[{"clientLanguage":["python"],"serviceConfig":{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"PythonService","waitForReady":true}]}]}}]',
+      type: TXT}
+- expected_addrs:
+  - {address: '1.2.3.4:443', is_balancer: false}
+  expected_chosen_service_config: null
+  expected_lb_policy: null
+  record_to_resolve: ipv4-cpp-config-has-zero-percentage
+  records:
+    ipv4-cpp-config-has-zero-percentage:
+    - {TTL: '2100', data: 1.2.3.4, type: A}
+    - {TTL: '2100', data: 'grpc_config=[{"percentage":0,"serviceConfig":{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"CppService","waitForReady":true}]}]}}]',
+      type: TXT}
+- expected_addrs:
+  - {address: '1.2.3.4:443', is_balancer: false}
+  expected_chosen_service_config: '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"CppService","waitForReady":true}]}]}'
+  expected_lb_policy: round_robin
+  record_to_resolve: ipv4-second-language-is-cpp
+  records:
+    ipv4-second-language-is-cpp:
+    - {TTL: '2100', data: 1.2.3.4, type: A}
+    - {TTL: '2100', data: 'grpc_config=[{"clientLanguage":["go"],"serviceConfig":{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"GoService","waitForReady":true}]}]}},{"clientLanguage":["c++"],"serviceConfig":{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"CppService","waitForReady":true}]}]}}]',
+      type: TXT}
+- expected_addrs:
+  - {address: '1.2.3.4:443', is_balancer: false}
+  expected_chosen_service_config: '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"AlwaysPickedService","waitForReady":true}]}]}'
+  expected_lb_policy: round_robin
+  record_to_resolve: ipv4-config-with-percentages
+  records:
+    ipv4-config-with-percentages:
+    - {TTL: '2100', data: 1.2.3.4, type: A}
+    - {TTL: '2100', data: 'grpc_config=[{"percentage":0,"serviceConfig":{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"NeverPickedService","waitForReady":true}]}]}},{"percentage":100,"serviceConfig":{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"AlwaysPickedService","waitForReady":true}]}]}}]',
+      type: TXT}
+- expected_addrs:
+  - {address: '1.2.3.4:1234', is_balancer: true}
+  - {address: '1.2.3.4:443', is_balancer: false}
+  expected_chosen_service_config: null
+  expected_lb_policy: null
+  record_to_resolve: srv-ipv4-target-has-backend-and-balancer
+  records:
+    _grpclb._tcp.srv-ipv4-target-has-backend-and-balancer:
+    - {TTL: '2100', data: 0 0 1234 balancer-for-ipv4-has-backend-and-balancer, type: SRV}
+    balancer-for-ipv4-has-backend-and-balancer:
+    - {TTL: '2100', data: 1.2.3.4, type: A}
+    srv-ipv4-target-has-backend-and-balancer:
+    - {TTL: '2100', data: 1.2.3.4, type: A}
+- expected_addrs:
+  - {address: '[2607:f8b0:400a:801::1002]:1234', is_balancer: true}
+  - {address: '[2607:f8b0:400a:801::1002]:443', is_balancer: false}
+  expected_chosen_service_config: null
+  expected_lb_policy: null
+  record_to_resolve: srv-ipv6-target-has-backend-and-balancer
+  records:
+    _grpclb._tcp.srv-ipv6-target-has-backend-and-balancer:
+    - {TTL: '2100', data: 0 0 1234 balancer-for-ipv6-has-backend-and-balancer, type: SRV}
+    balancer-for-ipv6-has-backend-and-balancer:
+    - {TTL: '2100', data: '2607:f8b0:400a:801::1002', type: AAAA}
+    srv-ipv6-target-has-backend-and-balancer:
+    - {TTL: '2100', data: '2607:f8b0:400a:801::1002', type: AAAA}
+
+resolver_component_tests_TODO:
+- 'TODO: enable this large-txt-record test once working. (it is much longer than 512
+  bytes, likely to cause use of TCP even if max payload for UDP is changed somehow,
+  e.g. via notes in RFC 2671)'
+- expected_addrs:
+  - {address: '1.2.3.4:443', is_balancer: false}
+  expected_chosen_service_config: '{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooTwo","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooThree","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooFour","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooFive","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooSix","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooSeven","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooEight","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooNine","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooTen","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooEleven","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooTwelve","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooTwelve","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooTwelve","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooTwelve","service":"SimpleService","waitForReady":true}]}]}'
+  expected_lb_policy: null
+  record_to_resolve: srv-ipv6-target-has-backend-and-balancer
+  record_to_resolve: ipv4-config-causing-fallback-to-tcp
+  records:
+    ipv4-config-causing-fallback-to-tcp:
+    - {TTL: '2100', data: 1.2.3.4, type: A}
+    - {TTL: '2100', data: 'grpc_config=[{"serviceConfig":{"loadBalancingPolicy":"round_robin","methodConfig":[{"name":[{"method":"Foo","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooTwo","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooThree","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooFour","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooFive","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooSix","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooSeven","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooEight","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooNine","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooTen","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooEleven","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooTwelve","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooTwelve","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooTwelve","service":"SimpleService","waitForReady":true}]},{"name":[{"method":"FooTwelve","service":"SimpleService","waitForReady":true}]}]}}]',
+      type: TXT}
diff --git a/test/cpp/naming/test_dns_server.py b/test/cpp/naming/test_dns_server.py
new file mode 100755
index 00000000000..9d4b89cffb5
--- /dev/null
+++ b/test/cpp/naming/test_dns_server.py
@@ -0,0 +1,134 @@
+#!/usr/bin/env python2.7
+# Copyright 2015 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Starts a local DNS server for use in tests"""
+
+import argparse
+import sys
+import yaml
+import signal
+import os
+
+import twisted
+import twisted.internet
+import twisted.internet.reactor
+import twisted.internet.threads
+import twisted.internet.defer
+import twisted.internet.protocol
+import twisted.names
+import twisted.names.client
+import twisted.names.dns
+import twisted.names.server
+from twisted.names import client, server, common, authority, dns
+import argparse
+
+_SERVER_HEALTH_CHECK_RECORD_NAME = 'health-check-local-dns-server-is-alive.resolver-tests.grpctestingexp' # missing end '.' for twisted syntax
+_SERVER_HEALTH_CHECK_RECORD_DATA = '123.123.123.123'
+
+class NoFileAuthority(authority.FileAuthority):
+  def __init__(self, soa, records):
+    # skip FileAuthority
+    common.ResolverBase.__init__(self)
+    self.soa = soa
+    self.records = records
+
+def start_local_dns_server(args):
+  all_records = {}
+  def _push_record(name, r):
+    print('pushing record: |%s|' % name)
+    if all_records.get(name) is not None:
+      all_records[name].append(r)
+      return
+    all_records[name] = [r]
+
+  def _maybe_split_up_txt_data(name, txt_data, r_ttl):
+    start = 0
+    txt_data_list = []
+    while len(txt_data[start:]) > 0:
+      next_read = len(txt_data[start:])
+      if next_read > 255:
+        next_read = 255
+      txt_data_list.append(txt_data[start:start+next_read])
+      start += next_read
+    _push_record(name, dns.Record_TXT(*txt_data_list, ttl=r_ttl))
+
+  with open(args.records_config_path) as config:
+    test_records_config = yaml.load(config)
+  common_zone_name = test_records_config['resolver_component_tests_common_zone_name']
+  for group in test_records_config['resolver_component_tests']:
+    for name in group['records'].keys():
+      for record in group['records'][name]:
+        r_type = record['type']
+        r_data = record['data']
+        r_ttl = int(record['TTL'])
+        record_full_name = '%s.%s' % (name, common_zone_name)
+        assert record_full_name[-1] == '.'
+        record_full_name = record_full_name[:-1]
+        if r_type == 'A':
+          _push_record(record_full_name, dns.Record_A(r_data, ttl=r_ttl))
+        if r_type == 'AAAA':
+          _push_record(record_full_name, dns.Record_AAAA(r_data, ttl=r_ttl))
+        if r_type == 'SRV':
+          p, w, port, target = r_data.split(' ')
+          p = int(p)
+          w = int(w)
+          port = int(port)
+          target_full_name = '%s.%s' % (target, common_zone_name)
+          r_data = '%s %s %s %s' % (p, w, port, target_full_name)
+          _push_record(record_full_name, dns.Record_SRV(p, w, port, target_full_name, ttl=r_ttl))
+        if r_type == 'TXT':
+          _maybe_split_up_txt_data(record_full_name, r_data, r_ttl)
+  # Server health check record
+  _push_record(_SERVER_HEALTH_CHECK_RECORD_NAME, dns.Record_A(_SERVER_HEALTH_CHECK_RECORD_DATA, ttl=0))
+  soa_record = dns.Record_SOA(mname = common_zone_name)
+  test_domain_com = NoFileAuthority(
+    soa = (common_zone_name, soa_record),
+    records = all_records,
+  )
+  server = twisted.names.server.DNSServerFactory(
+      authorities=[test_domain_com], verbose=2)
+  server.noisy = 2
+  twisted.internet.reactor.listenTCP(args.port, server)
+  dns_proto = twisted.names.dns.DNSDatagramProtocol(server)
+  dns_proto.noisy = 2
+  twisted.internet.reactor.listenUDP(args.port, dns_proto)
+  print('starting local dns server on 127.0.0.1:%s' % args.port)
+  print('starting twisted.internet.reactor')
+  twisted.internet.reactor.suggestThreadPoolSize(1)
+  twisted.internet.reactor.run()
+
+def _quit_on_signal(signum, _frame):
+  print('Received SIGNAL %d. Quitting with exit code 0' % signum)
+  twisted.internet.reactor.stop()
+  sys.stdout.flush()
+  sys.exit(0)
+
+def main():
+  argp = argparse.ArgumentParser(description='Local DNS Server for resolver tests')
+  argp.add_argument('-p', '--port', default=None, type=int,
+                    help='Port for DNS server to listen on for TCP and UDP.')
+  argp.add_argument('-r', '--records_config_path', default=None, type=str,
+                    help=('Directory of resolver_test_record_groups.yaml file. '
+                          'Defauls to path needed when the test is invoked as part of run_tests.py.'))
+  args = argp.parse_args()
+  signal.signal(signal.SIGALRM, _quit_on_signal)
+  signal.signal(signal.SIGTERM, _quit_on_signal)
+  signal.signal(signal.SIGINT, _quit_on_signal)
+  # Prevent zombies. Tests that use this server are short-lived.
+  signal.alarm(2 * 60)
+  start_local_dns_server(args)
+
+if __name__ == '__main__':
+  main()
diff --git a/tools/buildgen/generate_build_additions.sh b/tools/buildgen/generate_build_additions.sh
index 7649145f860..693c02fdb2c 100644
--- a/tools/buildgen/generate_build_additions.sh
+++ b/tools/buildgen/generate_build_additions.sh
@@ -24,6 +24,7 @@ gen_build_yaml_dirs="  \
   test/core/bad_client \
   test/core/bad_ssl    \
   test/core/end2end    \
+  test/cpp/naming \
   test/cpp/qps"
 gen_build_files=""
 for gen_build_yaml in $gen_build_yaml_dirs
diff --git a/tools/dockerfile/interoptest/grpc_interop_csharp/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_csharp/Dockerfile
index 4ccfbc43c30..dbf58023c53 100644
--- a/tools/dockerfile/interoptest/grpc_interop_csharp/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_csharp/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -61,7 +62,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 #================
 # C# dependencies
diff --git a/tools/dockerfile/interoptest/grpc_interop_cxx/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_cxx/Dockerfile
index 824ecf4604a..7cfe98cbc84 100644
--- a/tools/dockerfile/interoptest/grpc_interop_cxx/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_cxx/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -61,7 +62,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 #=================
 # C++ dependencies
diff --git a/tools/dockerfile/interoptest/grpc_interop_go/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_go/Dockerfile
index 5f7bedde735..febe2fa251b 100644
--- a/tools/dockerfile/interoptest/grpc_interop_go/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_go/Dockerfile
@@ -30,7 +30,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 # Define the default command.
 CMD ["bash"]
diff --git a/tools/dockerfile/interoptest/grpc_interop_go1.7/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_go1.7/Dockerfile
index 2bfa87c4ea2..3a516cbb62a 100644
--- a/tools/dockerfile/interoptest/grpc_interop_go1.7/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_go1.7/Dockerfile
@@ -30,7 +30,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 # Define the default command.
 CMD ["bash"]
diff --git a/tools/dockerfile/interoptest/grpc_interop_go1.8/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_go1.8/Dockerfile
index 96391372cab..acb640a81dc 100644
--- a/tools/dockerfile/interoptest/grpc_interop_go1.8/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_go1.8/Dockerfile
@@ -30,7 +30,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 # Define the default command.
 CMD ["bash"]
diff --git a/tools/dockerfile/interoptest/grpc_interop_http2/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_http2/Dockerfile
index 27a924343ff..354b7bfdb59 100644
--- a/tools/dockerfile/interoptest/grpc_interop_http2/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_http2/Dockerfile
@@ -30,7 +30,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 RUN pip install twisted h2==2.6.1 hyper
 
diff --git a/tools/dockerfile/interoptest/grpc_interop_java/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_java/Dockerfile
index 264a0f92713..92a542ff76b 100644
--- a/tools/dockerfile/interoptest/grpc_interop_java/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_java/Dockerfile
@@ -45,7 +45,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 
 # Trigger download of as many Gradle artifacts as possible.
diff --git a/tools/dockerfile/interoptest/grpc_interop_java_oracle8/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_java_oracle8/Dockerfile
index 264a0f92713..92a542ff76b 100644
--- a/tools/dockerfile/interoptest/grpc_interop_java_oracle8/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_java_oracle8/Dockerfile
@@ -45,7 +45,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 
 # Trigger download of as many Gradle artifacts as possible.
diff --git a/tools/dockerfile/interoptest/grpc_interop_node/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_node/Dockerfile
index c59b12d1556..4343d56cb49 100644
--- a/tools/dockerfile/interoptest/grpc_interop_node/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_node/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -61,7 +62,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 #==================
 # Node dependencies
diff --git a/tools/dockerfile/interoptest/grpc_interop_php/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_php/Dockerfile
index f859a465149..d6e229f84a2 100644
--- a/tools/dockerfile/interoptest/grpc_interop_php/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_php/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
diff --git a/tools/dockerfile/interoptest/grpc_interop_python/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_python/Dockerfile
index 42b1107c119..271c6e75e9d 100644
--- a/tools/dockerfile/interoptest/grpc_interop_python/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_python/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -61,7 +62,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 # Prepare ccache
 RUN ln -s /usr/bin/ccache /usr/local/bin/gcc
diff --git a/tools/dockerfile/interoptest/grpc_interop_ruby/Dockerfile b/tools/dockerfile/interoptest/grpc_interop_ruby/Dockerfile
index 3c744b434e6..7bcada68e0a 100644
--- a/tools/dockerfile/interoptest/grpc_interop_ruby/Dockerfile
+++ b/tools/dockerfile/interoptest/grpc_interop_ruby/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -61,7 +62,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 #==================
 # Ruby dependencies
diff --git a/tools/dockerfile/test/csharp_jessie_x64/Dockerfile b/tools/dockerfile/test/csharp_jessie_x64/Dockerfile
index 60dc7eb21aa..40d46fcf58b 100644
--- a/tools/dockerfile/test/csharp_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/csharp_jessie_x64/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -65,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 #================
 # C# dependencies
diff --git a/tools/dockerfile/test/cxx_jessie_x64/Dockerfile b/tools/dockerfile/test/cxx_jessie_x64/Dockerfile
index f9622dd7577..888a37baca7 100644
--- a/tools/dockerfile/test/cxx_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/cxx_jessie_x64/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -65,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 #=================
 # C++ dependencies
diff --git a/tools/dockerfile/test/cxx_jessie_x86/Dockerfile b/tools/dockerfile/test/cxx_jessie_x86/Dockerfile
index 2d396ce2ff0..319f1e18893 100644
--- a/tools/dockerfile/test/cxx_jessie_x86/Dockerfile
+++ b/tools/dockerfile/test/cxx_jessie_x86/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -65,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 #=================
 # C++ dependencies
diff --git a/tools/dockerfile/test/cxx_ubuntu1404_x64/Dockerfile b/tools/dockerfile/test/cxx_ubuntu1404_x64/Dockerfile
index 349a6eff837..61f005d9da3 100644
--- a/tools/dockerfile/test/cxx_ubuntu1404_x64/Dockerfile
+++ b/tools/dockerfile/test/cxx_ubuntu1404_x64/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -65,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 #=================
 # C++ dependencies
diff --git a/tools/dockerfile/test/cxx_ubuntu1604_x64/Dockerfile b/tools/dockerfile/test/cxx_ubuntu1604_x64/Dockerfile
index bccfdba7cd3..f35247eccb5 100644
--- a/tools/dockerfile/test/cxx_ubuntu1604_x64/Dockerfile
+++ b/tools/dockerfile/test/cxx_ubuntu1604_x64/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -65,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 #=================
 # C++ dependencies
diff --git a/tools/dockerfile/test/fuzzer/Dockerfile b/tools/dockerfile/test/fuzzer/Dockerfile
index 94c37b3f631..ce1badfeb1b 100644
--- a/tools/dockerfile/test/fuzzer/Dockerfile
+++ b/tools/dockerfile/test/fuzzer/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -65,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 #=================
 # C++ dependencies
diff --git a/tools/dockerfile/test/multilang_jessie_x64/Dockerfile b/tools/dockerfile/test/multilang_jessie_x64/Dockerfile
index b7373b5d9c3..59fe4d8f93b 100644
--- a/tools/dockerfile/test/multilang_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/multilang_jessie_x64/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -122,7 +123,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 # Install coverage for Python test coverage reporting
 RUN pip install coverage
diff --git a/tools/dockerfile/test/node_jessie_x64/Dockerfile b/tools/dockerfile/test/node_jessie_x64/Dockerfile
index 31602e594ec..103be8412b4 100644
--- a/tools/dockerfile/test/node_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/node_jessie_x64/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -76,7 +77,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 #==================
 # Node dependencies
diff --git a/tools/dockerfile/test/php7_jessie_x64/Dockerfile b/tools/dockerfile/test/php7_jessie_x64/Dockerfile
index e79305bb27b..f6d426bcd6a 100644
--- a/tools/dockerfile/test/php7_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/php7_jessie_x64/Dockerfile
@@ -77,7 +77,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 # Prepare ccache
 RUN ln -s /usr/bin/ccache /usr/local/bin/gcc
diff --git a/tools/dockerfile/test/php_jessie_x64/Dockerfile b/tools/dockerfile/test/php_jessie_x64/Dockerfile
index 245a6423678..ae82a8d99f1 100644
--- a/tools/dockerfile/test/php_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/php_jessie_x64/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -65,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 #=================
 # PHP dependencies
diff --git a/tools/dockerfile/test/python_jessie_x64/Dockerfile b/tools/dockerfile/test/python_jessie_x64/Dockerfile
index 5093b793b06..d5d781cd1ac 100644
--- a/tools/dockerfile/test/python_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/python_jessie_x64/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -65,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 # Prepare ccache
 RUN ln -s /usr/bin/ccache /usr/local/bin/gcc
diff --git a/tools/dockerfile/test/python_pyenv_x64/Dockerfile b/tools/dockerfile/test/python_pyenv_x64/Dockerfile
index ff8f0231cb8..3b4ad12b6d9 100644
--- a/tools/dockerfile/test/python_pyenv_x64/Dockerfile
+++ b/tools/dockerfile/test/python_pyenv_x64/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -65,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 # Install dependencies for pyenv
 RUN apt-get update && apt-get install -y \
diff --git a/tools/dockerfile/test/ruby_jessie_x64/Dockerfile b/tools/dockerfile/test/ruby_jessie_x64/Dockerfile
index d77917c87fa..3d879bb0c90 100644
--- a/tools/dockerfile/test/ruby_jessie_x64/Dockerfile
+++ b/tools/dockerfile/test/ruby_jessie_x64/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -65,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 #==================
 # Ruby dependencies
diff --git a/tools/dockerfile/test/sanity/Dockerfile b/tools/dockerfile/test/sanity/Dockerfile
index 0f2f9ede58c..44732a5ae42 100644
--- a/tools/dockerfile/test/sanity/Dockerfile
+++ b/tools/dockerfile/test/sanity/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
   bzip2 \
   ccache \
   curl \
+  dnsutils \
   gcc \
   gcc-multilib \
   git \
@@ -65,7 +66,7 @@ RUN apt-get update && apt-get install -y \
 # Install Python packages from PyPI
 RUN pip install pip --upgrade
 RUN pip install virtualenv
-RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.2.0 six==1.10.0 twisted==17.5.0
 
 #========================
 # Sanity test dependencies
diff --git a/tools/internal_ci/helper_scripts/prepare_build_macos_rc b/tools/internal_ci/helper_scripts/prepare_build_macos_rc
index dd2741e595b..3319aa4394f 100644
--- a/tools/internal_ci/helper_scripts/prepare_build_macos_rc
+++ b/tools/internal_ci/helper_scripts/prepare_build_macos_rc
@@ -46,7 +46,7 @@ pod repo update  # needed by python
 # python
 brew install coreutils  # we need grealpath
 pip install virtualenv --user python
-pip install -U six tox setuptools --user python
+pip install -U six tox setuptools twisted pyyaml --user python
 export PYTHONPATH=/Library/Python/3.4/site-packages
 
 # set xcode version for Obj-C tests
diff --git a/tools/run_tests/generated/sources_and_headers.json b/tools/run_tests/generated/sources_and_headers.json
index 2f6e34bfb38..8d42c3e4328 100644
--- a/tools/run_tests/generated/sources_and_headers.json
+++ b/tools/run_tests/generated/sources_and_headers.json
@@ -5627,6 +5627,86 @@
     "third_party": false, 
     "type": "target"
   }, 
+  {
+    "deps": [
+      "gpr", 
+      "gpr_test_util", 
+      "grpc++_test_config", 
+      "grpc++_test_util_unsecure", 
+      "grpc++_unsecure", 
+      "grpc_test_util_unsecure", 
+      "grpc_unsecure"
+    ], 
+    "headers": [], 
+    "is_filegroup": false, 
+    "language": "c++", 
+    "name": "resolver_component_test_unsecure", 
+    "src": [
+      "test/cpp/naming/resolver_component_test.cc"
+    ], 
+    "third_party": false, 
+    "type": "target"
+  }, 
+  {
+    "deps": [
+      "gpr", 
+      "gpr_test_util", 
+      "grpc", 
+      "grpc++", 
+      "grpc++_test_config", 
+      "grpc++_test_util", 
+      "grpc_test_util"
+    ], 
+    "headers": [], 
+    "is_filegroup": false, 
+    "language": "c++", 
+    "name": "resolver_component_test", 
+    "src": [
+      "test/cpp/naming/resolver_component_test.cc"
+    ], 
+    "third_party": false, 
+    "type": "target"
+  }, 
+  {
+    "deps": [
+      "gpr", 
+      "gpr_test_util", 
+      "grpc", 
+      "grpc++", 
+      "grpc++_test_config", 
+      "grpc++_test_util", 
+      "grpc_test_util"
+    ], 
+    "headers": [], 
+    "is_filegroup": false, 
+    "language": "c++", 
+    "name": "resolver_component_tests_runner_invoker_unsecure", 
+    "src": [
+      "test/cpp/naming/resolver_component_tests_runner_invoker.cc"
+    ], 
+    "third_party": false, 
+    "type": "target"
+  }, 
+  {
+    "deps": [
+      "gpr", 
+      "gpr_test_util", 
+      "grpc", 
+      "grpc++", 
+      "grpc++_test_config", 
+      "grpc++_test_util", 
+      "grpc_test_util"
+    ], 
+    "headers": [], 
+    "is_filegroup": false, 
+    "language": "c++", 
+    "name": "resolver_component_tests_runner_invoker", 
+    "src": [
+      "test/cpp/naming/resolver_component_tests_runner_invoker.cc"
+    ], 
+    "third_party": false, 
+    "type": "target"
+  }, 
   {
     "deps": [
       "gpr", 
diff --git a/tools/run_tests/generated/tests.json b/tools/run_tests/generated/tests.json
index 45d7145e8e3..72dfbc0b982 100644
--- a/tools/run_tests/generated/tests.json
+++ b/tools/run_tests/generated/tests.json
@@ -4404,6 +4404,52 @@
       "posix"
     ]
   }, 
+  {
+    "args": [
+      "--test_bin_name=resolver_component_test_unsecure", 
+      "--running_under_bazel=false"
+    ], 
+    "ci_platforms": [
+      "linux", 
+      "mac", 
+      "posix"
+    ], 
+    "cpu_cost": 1.0, 
+    "exclude_configs": [], 
+    "exclude_iomgrs": [], 
+    "flaky": false, 
+    "gtest": false, 
+    "language": "c++", 
+    "name": "resolver_component_tests_runner_invoker_unsecure", 
+    "platforms": [
+      "linux", 
+      "mac", 
+      "posix"
+    ]
+  }, 
+  {
+    "args": [
+      "--test_bin_name=resolver_component_test", 
+      "--running_under_bazel=false"
+    ], 
+    "ci_platforms": [
+      "linux", 
+      "mac", 
+      "posix"
+    ], 
+    "cpu_cost": 1.0, 
+    "exclude_configs": [], 
+    "exclude_iomgrs": [], 
+    "flaky": false, 
+    "gtest": false, 
+    "language": "c++", 
+    "name": "resolver_component_tests_runner_invoker", 
+    "platforms": [
+      "linux", 
+      "mac", 
+      "posix"
+    ]
+  }, 
   {
     "args": [
       "third_party/boringssl/crypto/aes/aes_tests.txt"

From b2a54ac4cb95742a11325c923f63a8aa1dd145e0 Mon Sep 17 00:00:00 2001
From: Yash Tibrewal <yashkt@google.com>
Date: Wed, 13 Sep 2017 10:18:07 -0700
Subject: [PATCH 09/20] Reverting suffixes and changing field names instead

---
 src/core/lib/iomgr/ev_epoll1_linux.c  |  54 ++++----
 src/core/lib/iomgr/ev_epollex_linux.c | 186 +++++++++++++-------------
 src/core/lib/surface/call.c           |  66 ++++-----
 src/core/lib/surface/call.h           |   2 +-
 src/core/lib/surface/channel.c        |   2 +-
 5 files changed, 157 insertions(+), 153 deletions(-)

diff --git a/src/core/lib/iomgr/ev_epoll1_linux.c b/src/core/lib/iomgr/ev_epoll1_linux.c
index 6946a2cbf52..0d57833d859 100644
--- a/src/core/lib/iomgr/ev_epoll1_linux.c
+++ b/src/core/lib/iomgr/ev_epoll1_linux.c
@@ -130,9 +130,9 @@ static void fd_global_shutdown(void);
  * Pollset Declarations
  */
 
-typedef enum { UNKICKED, KICKED, DESIGNATED_POLLER } kick_state_t;
+typedef enum { UNKICKED, KICKED, DESIGNATED_POLLER } kick_state;
 
-static const char *kick_state_string(kick_state_t st) {
+static const char *kick_state_string(kick_state st) {
   switch (st) {
     case UNKICKED:
       return "UNKICKED";
@@ -145,7 +145,7 @@ static const char *kick_state_string(kick_state_t st) {
 }
 
 struct grpc_pollset_worker {
-  kick_state_t kick_state;
+  kick_state state;
   int kick_state_mutator;  // which line of code last changed kick state
   bool initialized_cv;
   grpc_pollset_worker *next;
@@ -154,9 +154,9 @@ struct grpc_pollset_worker {
   grpc_closure_list schedule_on_end_work;
 };
 
-#define SET_KICK_STATE(worker, state)        \
+#define SET_KICK_STATE(worker, kick_state)   \
   do {                                       \
-    (worker)->kick_state = (state);          \
+    (worker)->state = (kick_state);          \
     (worker)->kick_state_mutator = __LINE__; \
   } while (false)
 
@@ -508,7 +508,7 @@ static grpc_error *pollset_kick_all(grpc_pollset *pollset) {
   if (pollset->root_worker != NULL) {
     grpc_pollset_worker *worker = pollset->root_worker;
     do {
-      switch (worker->kick_state) {
+      switch (worker->state) {
         case KICKED:
           break;
         case UNKICKED:
@@ -688,7 +688,7 @@ static bool begin_worker(grpc_pollset *pollset, grpc_pollset_worker *worker,
     gpr_mu_lock(&pollset->mu);
     if (GRPC_TRACER_ON(grpc_polling_trace)) {
       gpr_log(GPR_ERROR, "PS:%p BEGIN_REORG:%p kick_state=%s is_reassigning=%d",
-              pollset, worker, kick_state_string(worker->kick_state),
+              pollset, worker, kick_state_string(worker->state),
               is_reassigning);
     }
     if (pollset->seen_inactive) {
@@ -708,12 +708,12 @@ static bool begin_worker(grpc_pollset *pollset, grpc_pollset_worker *worker,
          at this point is if it were "kicked specifically". Since the worker has
          not added itself to the pollset yet (by calling worker_insert()), it is
          not visible in the "kick any" path yet */
-      if (worker->kick_state == UNKICKED) {
+      if (worker->state == UNKICKED) {
         pollset->seen_inactive = false;
         if (neighborhood->active_root == NULL) {
           neighborhood->active_root = pollset->next = pollset->prev = pollset;
           /* Make this the designated poller if there isn't one already */
-          if (worker->kick_state == UNKICKED &&
+          if (worker->state == UNKICKED &&
               gpr_atm_no_barrier_cas(&g_active_poller, 0, (gpr_atm)worker)) {
             SET_KICK_STATE(worker, DESIGNATED_POLLER);
           }
@@ -733,19 +733,19 @@ static bool begin_worker(grpc_pollset *pollset, grpc_pollset_worker *worker,
 
   worker_insert(pollset, worker);
   pollset->begin_refs--;
-  if (worker->kick_state == UNKICKED && !pollset->kicked_without_poller) {
+  if (worker->state == UNKICKED && !pollset->kicked_without_poller) {
     GPR_ASSERT(gpr_atm_no_barrier_load(&g_active_poller) != (gpr_atm)worker);
     worker->initialized_cv = true;
     gpr_cv_init(&worker->cv);
-    while (worker->kick_state == UNKICKED && !pollset->shutting_down) {
+    while (worker->state == UNKICKED && !pollset->shutting_down) {
       if (GRPC_TRACER_ON(grpc_polling_trace)) {
         gpr_log(GPR_ERROR, "PS:%p BEGIN_WAIT:%p kick_state=%s shutdown=%d",
-                pollset, worker, kick_state_string(worker->kick_state),
+                pollset, worker, kick_state_string(worker->state),
                 pollset->shutting_down);
       }
 
       if (gpr_cv_wait(&worker->cv, &pollset->mu, deadline) &&
-          worker->kick_state == UNKICKED) {
+          worker->state == UNKICKED) {
         /* If gpr_cv_wait returns true (i.e a timeout), pretend that the worker
            received a kick */
         SET_KICK_STATE(worker, KICKED);
@@ -758,7 +758,7 @@ static bool begin_worker(grpc_pollset *pollset, grpc_pollset_worker *worker,
     gpr_log(GPR_ERROR,
             "PS:%p BEGIN_DONE:%p kick_state=%s shutdown=%d "
             "kicked_without_poller: %d",
-            pollset, worker, kick_state_string(worker->kick_state),
+            pollset, worker, kick_state_string(worker->state),
             pollset->shutting_down, pollset->kicked_without_poller);
   }
 
@@ -778,7 +778,7 @@ static bool begin_worker(grpc_pollset *pollset, grpc_pollset_worker *worker,
   }
 
   GPR_TIMER_END("begin_worker", 0);
-  return worker->kick_state == DESIGNATED_POLLER && !pollset->shutting_down;
+  return worker->state == DESIGNATED_POLLER && !pollset->shutting_down;
 }
 
 static bool check_neighborhood_for_available_poller(
@@ -795,7 +795,7 @@ static bool check_neighborhood_for_available_poller(
     grpc_pollset_worker *inspect_worker = inspect->root_worker;
     if (inspect_worker != NULL) {
       do {
-        switch (inspect_worker->kick_state) {
+        switch (inspect_worker->state) {
           case UNKICKED:
             if (gpr_atm_no_barrier_cas(&g_active_poller, 0,
                                        (gpr_atm)inspect_worker)) {
@@ -858,7 +858,7 @@ static void end_worker(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   grpc_closure_list_move(&worker->schedule_on_end_work,
                          &exec_ctx->closure_list);
   if (gpr_atm_no_barrier_load(&g_active_poller) == (gpr_atm)worker) {
-    if (worker->next != worker && worker->next->kick_state == UNKICKED) {
+    if (worker->next != worker && worker->next->state == UNKICKED) {
       if (GRPC_TRACER_ON(grpc_polling_trace)) {
         gpr_log(GPR_DEBUG, " .. choose next poller to be peer %p", worker);
       }
@@ -993,14 +993,14 @@ static grpc_error *pollset_kick(grpc_pollset *pollset,
     gpr_strvec_add(&log, tmp);
     if (pollset->root_worker != NULL) {
       gpr_asprintf(&tmp, " {kick_state=%s next=%p {kick_state=%s}}",
-                   kick_state_string(pollset->root_worker->kick_state),
+                   kick_state_string(pollset->root_worker->state),
                    pollset->root_worker->next,
-                   kick_state_string(pollset->root_worker->next->kick_state));
+                   kick_state_string(pollset->root_worker->next->state));
       gpr_strvec_add(&log, tmp);
     }
     if (specific_worker != NULL) {
       gpr_asprintf(&tmp, " worker_kick_state=%s",
-                   kick_state_string(specific_worker->kick_state));
+                   kick_state_string(specific_worker->state));
       gpr_strvec_add(&log, tmp);
     }
     tmp = gpr_strvec_flatten(&log, NULL);
@@ -1020,13 +1020,13 @@ static grpc_error *pollset_kick(grpc_pollset *pollset,
         goto done;
       }
       grpc_pollset_worker *next_worker = root_worker->next;
-      if (root_worker->kick_state == KICKED) {
+      if (root_worker->state == KICKED) {
         if (GRPC_TRACER_ON(grpc_polling_trace)) {
           gpr_log(GPR_ERROR, " .. already kicked %p", root_worker);
         }
         SET_KICK_STATE(root_worker, KICKED);
         goto done;
-      } else if (next_worker->kick_state == KICKED) {
+      } else if (next_worker->state == KICKED) {
         if (GRPC_TRACER_ON(grpc_polling_trace)) {
           gpr_log(GPR_ERROR, " .. already kicked %p", next_worker);
         }
@@ -1043,7 +1043,7 @@ static grpc_error *pollset_kick(grpc_pollset *pollset,
         SET_KICK_STATE(root_worker, KICKED);
         ret_err = grpc_wakeup_fd_wakeup(&global_wakeup_fd);
         goto done;
-      } else if (next_worker->kick_state == UNKICKED) {
+      } else if (next_worker->state == UNKICKED) {
         if (GRPC_TRACER_ON(grpc_polling_trace)) {
           gpr_log(GPR_ERROR, " .. kicked %p", next_worker);
         }
@@ -1051,8 +1051,8 @@ static grpc_error *pollset_kick(grpc_pollset *pollset,
         SET_KICK_STATE(next_worker, KICKED);
         gpr_cv_signal(&next_worker->cv);
         goto done;
-      } else if (next_worker->kick_state == DESIGNATED_POLLER) {
-        if (root_worker->kick_state != DESIGNATED_POLLER) {
+      } else if (next_worker->state == DESIGNATED_POLLER) {
+        if (root_worker->state != DESIGNATED_POLLER) {
           if (GRPC_TRACER_ON(grpc_polling_trace)) {
             gpr_log(
                 GPR_ERROR,
@@ -1074,7 +1074,7 @@ static grpc_error *pollset_kick(grpc_pollset *pollset,
           goto done;
         }
       } else {
-        GPR_ASSERT(next_worker->kick_state == KICKED);
+        GPR_ASSERT(next_worker->state == KICKED);
         SET_KICK_STATE(next_worker, KICKED);
         goto done;
       }
@@ -1088,7 +1088,7 @@ static grpc_error *pollset_kick(grpc_pollset *pollset,
     GPR_UNREACHABLE_CODE(goto done);
   }
 
-  if (specific_worker->kick_state == KICKED) {
+  if (specific_worker->state == KICKED) {
     if (GRPC_TRACER_ON(grpc_polling_trace)) {
       gpr_log(GPR_ERROR, " .. specific worker already kicked");
     }
diff --git a/src/core/lib/iomgr/ev_epollex_linux.c b/src/core/lib/iomgr/ev_epollex_linux.c
index df69025f1a3..9934f8d3299 100644
--- a/src/core/lib/iomgr/ev_epollex_linux.c
+++ b/src/core/lib/iomgr/ev_epollex_linux.c
@@ -97,12 +97,12 @@ static void pg_join(grpc_exec_ctx *exec_ctx, polling_group *pg,
  * pollable Declarations
  */
 
-typedef struct pollable_t {
+typedef struct pollable {
   polling_obj po;
   int epfd;
   grpc_wakeup_fd wakeup;
   grpc_pollset_worker *root_worker;
-} pollable_t;
+} pollable;
 
 static const char *polling_obj_type_string(polling_obj_type t) {
   switch (t) {
@@ -122,7 +122,7 @@ static const char *polling_obj_type_string(polling_obj_type t) {
   return "<invalid>";
 }
 
-static char *pollable_desc(pollable_t *p) {
+static char *pollable_desc(pollable *p) {
   char *out;
   gpr_asprintf(&out, "type=%s group=%p epfd=%d wakeup=%d",
                polling_obj_type_string(p->po.type), p->po.group, p->epfd,
@@ -130,19 +130,19 @@ static char *pollable_desc(pollable_t *p) {
   return out;
 }
 
-static pollable_t g_empty_pollable;
+static pollable g_empty_pollable;
 
-static void pollable_init(pollable_t *p, polling_obj_type type);
-static void pollable_destroy(pollable_t *p);
+static void pollable_init(pollable *p, polling_obj_type type);
+static void pollable_destroy(pollable *p);
 /* ensure that p->epfd, p->wakeup are initialized; p->po.mu must be held */
-static grpc_error *pollable_materialize(pollable_t *p);
+static grpc_error *pollable_materialize(pollable *p);
 
 /*******************************************************************************
  * Fd Declarations
  */
 
 struct grpc_fd {
-  pollable_t pollable;
+  pollable pollable_obj;
   int fd;
   /* refst format:
        bit 0    : 1=Active / 0=Orphaned
@@ -193,15 +193,15 @@ struct grpc_pollset_worker {
   pollset_worker_link links[POLLSET_WORKER_LINK_COUNT];
   gpr_cv cv;
   grpc_pollset *pollset;
-  pollable_t *pollable;
+  pollable *pollable_obj;
 };
 
 #define MAX_EPOLL_EVENTS 100
 #define MAX_EPOLL_EVENTS_HANDLED_EACH_POLL_CALL 5
 
 struct grpc_pollset {
-  pollable_t pollable;
-  pollable_t *current_pollable;
+  pollable pollable_obj;
+  pollable *current_pollable;
   int kick_alls_pending;
   bool kicked_without_poller;
   grpc_closure *shutdown_closure;
@@ -282,7 +282,7 @@ static void fd_destroy(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
   grpc_fd *fd = (grpc_fd *)arg;
   /* Add the fd to the freelist */
   grpc_iomgr_unregister_object(&fd->iomgr_object);
-  pollable_destroy(&fd->pollable);
+  pollable_destroy(&fd->pollable_obj);
   gpr_mu_destroy(&fd->orphaned_mu);
   gpr_mu_lock(&fd_freelist_mu);
   fd->freelist_next = fd_freelist;
@@ -343,7 +343,7 @@ static grpc_fd *fd_create(int fd, const char *name) {
     new_fd = (grpc_fd *)gpr_malloc(sizeof(grpc_fd));
   }
 
-  pollable_init(&new_fd->pollable, PO_FD);
+  pollable_init(&new_fd->pollable_obj, PO_FD);
 
   gpr_atm_rel_store(&new_fd->refst, (gpr_atm)1);
   new_fd->fd = fd;
@@ -385,7 +385,7 @@ static void fd_orphan(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
   bool is_fd_closed = already_closed;
   grpc_error *error = GRPC_ERROR_NONE;
 
-  gpr_mu_lock(&fd->pollable.po.mu);
+  gpr_mu_lock(&fd->pollable_obj.po.mu);
   gpr_mu_lock(&fd->orphaned_mu);
   fd->on_done_closure = on_done;
 
@@ -411,7 +411,7 @@ static void fd_orphan(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
   GRPC_CLOSURE_SCHED(exec_ctx, fd->on_done_closure, GRPC_ERROR_REF(error));
 
   gpr_mu_unlock(&fd->orphaned_mu);
-  gpr_mu_unlock(&fd->pollable.po.mu);
+  gpr_mu_unlock(&fd->pollable_obj.po.mu);
   UNREF_BY(exec_ctx, fd, 2, reason); /* Drop the reference */
   GRPC_LOG_IF_ERROR("fd_orphan", GRPC_ERROR_REF(error));
   GRPC_ERROR_UNREF(error);
@@ -451,13 +451,13 @@ static void fd_notify_on_write(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
  * Pollable Definitions
  */
 
-static void pollable_init(pollable_t *p, polling_obj_type type) {
+static void pollable_init(pollable *p, polling_obj_type type) {
   po_init(&p->po, type);
   p->root_worker = NULL;
   p->epfd = -1;
 }
 
-static void pollable_destroy(pollable_t *p) {
+static void pollable_destroy(pollable *p) {
   po_destroy(&p->po);
   if (p->epfd != -1) {
     close(p->epfd);
@@ -466,7 +466,7 @@ static void pollable_destroy(pollable_t *p) {
 }
 
 /* ensure that p->epfd, p->wakeup are initialized; p->po.mu must be held */
-static grpc_error *pollable_materialize(pollable_t *p) {
+static grpc_error *pollable_materialize(pollable *p) {
   if (p->epfd == -1) {
     int new_epfd = epoll_create1(EPOLL_CLOEXEC);
     if (new_epfd < 0) {
@@ -492,7 +492,7 @@ static grpc_error *pollable_materialize(pollable_t *p) {
 }
 
 /* pollable must be materialized */
-static grpc_error *pollable_add_fd(pollable_t *p, grpc_fd *fd) {
+static grpc_error *pollable_add_fd(pollable *p, grpc_fd *fd) {
   grpc_error *error = GRPC_ERROR_NONE;
   static const char *err_desc = "pollable_add_fd";
   const int epfd = p->epfd;
@@ -557,30 +557,33 @@ static void do_kick_all(grpc_exec_ctx *exec_ctx, void *arg,
                         grpc_error *error_unused) {
   grpc_error *error = GRPC_ERROR_NONE;
   grpc_pollset *pollset = (grpc_pollset *)arg;
-  gpr_mu_lock(&pollset->pollable.po.mu);
+  gpr_mu_lock(&pollset->pollable_obj.po.mu);
   if (pollset->root_worker != NULL) {
     grpc_pollset_worker *worker = pollset->root_worker;
     do {
-      if (worker->pollable != &pollset->pollable) {
-        gpr_mu_lock(&worker->pollable->po.mu);
+      if (worker->pollable_obj != &pollset->pollable_obj) {
+        gpr_mu_lock(&worker->pollable_obj->po.mu);
       }
       if (worker->initialized_cv && worker != pollset->root_worker) {
         if (GRPC_TRACER_ON(grpc_polling_trace)) {
           gpr_log(GPR_DEBUG, "PS:%p kickall_via_cv %p (pollable %p vs %p)",
-                  pollset, worker, &pollset->pollable, worker->pollable);
+                  pollset, worker, &pollset->pollable_obj,
+                  worker->pollable_obj);
         }
         worker->kicked = true;
         gpr_cv_signal(&worker->cv);
       } else {
         if (GRPC_TRACER_ON(grpc_polling_trace)) {
           gpr_log(GPR_DEBUG, "PS:%p kickall_via_wakeup %p (pollable %p vs %p)",
-                  pollset, worker, &pollset->pollable, worker->pollable);
+                  pollset, worker, &pollset->pollable_obj,
+                  worker->pollable_obj);
         }
-        append_error(&error, grpc_wakeup_fd_wakeup(&worker->pollable->wakeup),
+        append_error(&error,
+                     grpc_wakeup_fd_wakeup(&worker->pollable_obj->wakeup),
                      "pollset_shutdown");
       }
-      if (worker->pollable != &pollset->pollable) {
-        gpr_mu_unlock(&worker->pollable->po.mu);
+      if (worker->pollable_obj != &pollset->pollable_obj) {
+        gpr_mu_unlock(&worker->pollable_obj->po.mu);
       }
 
       worker = worker->links[PWL_POLLSET].next;
@@ -588,7 +591,7 @@ static void do_kick_all(grpc_exec_ctx *exec_ctx, void *arg,
   }
   pollset->kick_alls_pending--;
   pollset_maybe_finish_shutdown(exec_ctx, pollset);
-  gpr_mu_unlock(&pollset->pollable.po.mu);
+  gpr_mu_unlock(&pollset->pollable_obj.po.mu);
   GRPC_LOG_IF_ERROR("kick_all", error);
 }
 
@@ -599,7 +602,7 @@ static void pollset_kick_all(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) {
                      GRPC_ERROR_NONE);
 }
 
-static grpc_error *pollset_kick_inner(grpc_pollset *pollset, pollable_t *p,
+static grpc_error *pollset_kick_inner(grpc_pollset *pollset, pollable *p,
                                       grpc_pollset_worker *specific_worker) {
   if (GRPC_TRACER_ON(grpc_polling_trace)) {
     gpr_log(GPR_DEBUG,
@@ -664,24 +667,24 @@ static grpc_error *pollset_kick_inner(grpc_pollset *pollset, pollable_t *p,
 /* p->po.mu must be held before calling this function */
 static grpc_error *pollset_kick(grpc_pollset *pollset,
                                 grpc_pollset_worker *specific_worker) {
-  pollable_t *p = pollset->current_pollable;
-  if (p != &pollset->pollable) {
+  pollable *p = pollset->current_pollable;
+  if (p != &pollset->pollable_obj) {
     gpr_mu_lock(&p->po.mu);
   }
   grpc_error *error = pollset_kick_inner(pollset, p, specific_worker);
-  if (p != &pollset->pollable) {
+  if (p != &pollset->pollable_obj) {
     gpr_mu_unlock(&p->po.mu);
   }
   return error;
 }
 
 static void pollset_init(grpc_pollset *pollset, gpr_mu **mu) {
-  pollable_init(&pollset->pollable, PO_POLLSET);
+  pollable_init(&pollset->pollable_obj, PO_POLLSET);
   pollset->current_pollable = &g_empty_pollable;
   pollset->kicked_without_poller = false;
   pollset->shutdown_closure = NULL;
   pollset->root_worker = NULL;
-  *mu = &pollset->pollable.po.mu;
+  *mu = &pollset->pollable_obj.po.mu;
 }
 
 /* Convert a timespec to milliseconds:
@@ -729,8 +732,8 @@ static void fd_become_writable(grpc_exec_ctx *exec_ctx, grpc_fd *fd) {
 static grpc_error *fd_become_pollable_locked(grpc_fd *fd) {
   grpc_error *error = GRPC_ERROR_NONE;
   static const char *err_desc = "fd_become_pollable";
-  if (append_error(&error, pollable_materialize(&fd->pollable), err_desc)) {
-    append_error(&error, pollable_add_fd(&fd->pollable, fd), err_desc);
+  if (append_error(&error, pollable_materialize(&fd->pollable_obj), err_desc)) {
+    append_error(&error, pollable_add_fd(&fd->pollable_obj, fd), err_desc);
   }
   return error;
 }
@@ -744,8 +747,8 @@ static void pollset_shutdown(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   pollset_maybe_finish_shutdown(exec_ctx, pollset);
 }
 
-static bool pollset_is_pollable_fd(grpc_pollset *pollset, pollable_t *p) {
-  return p != &g_empty_pollable && p != &pollset->pollable;
+static bool pollset_is_pollable_fd(grpc_pollset *pollset, pollable *p) {
+  return p != &g_empty_pollable && p != &pollset->pollable_obj;
 }
 
 static grpc_error *pollset_process_events(grpc_exec_ctx *exec_ctx,
@@ -791,7 +794,7 @@ static grpc_error *pollset_process_events(grpc_exec_ctx *exec_ctx,
 
 /* pollset_shutdown is guaranteed to be called before pollset_destroy. */
 static void pollset_destroy(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) {
-  pollable_destroy(&pollset->pollable);
+  pollable_destroy(&pollset->pollable_obj);
   if (pollset_is_pollable_fd(pollset, pollset->current_pollable)) {
     UNREF_BY(exec_ctx, (grpc_fd *)pollset->current_pollable, 2,
              "pollset_pollable");
@@ -801,7 +804,7 @@ static void pollset_destroy(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) {
 }
 
 static grpc_error *pollset_epoll(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
-                                 pollable_t *p, gpr_timespec now,
+                                 pollable *p, gpr_timespec now,
                                  gpr_timespec deadline) {
   int timeout = poll_deadline_to_millis_timeout(deadline, now);
 
@@ -883,68 +886,69 @@ static bool begin_worker(grpc_pollset *pollset, grpc_pollset_worker *worker,
   worker->initialized_cv = false;
   worker->kicked = false;
   worker->pollset = pollset;
-  worker->pollable = pollset->current_pollable;
+  worker->pollable_obj = pollset->current_pollable;
 
-  if (pollset_is_pollable_fd(pollset, worker->pollable)) {
-    REF_BY((grpc_fd *)worker->pollable, 2, "one_poll");
+  if (pollset_is_pollable_fd(pollset, worker->pollable_obj)) {
+    REF_BY((grpc_fd *)worker->pollable_obj, 2, "one_poll");
   }
 
   worker_insert(&pollset->root_worker, PWL_POLLSET, worker);
-  if (!worker_insert(&worker->pollable->root_worker, PWL_POLLABLE, worker)) {
+  if (!worker_insert(&worker->pollable_obj->root_worker, PWL_POLLABLE,
+                     worker)) {
     worker->initialized_cv = true;
     gpr_cv_init(&worker->cv);
-    if (worker->pollable != &pollset->pollable) {
-      gpr_mu_unlock(&pollset->pollable.po.mu);
+    if (worker->pollable_obj != &pollset->pollable_obj) {
+      gpr_mu_unlock(&pollset->pollable_obj.po.mu);
     }
     if (GRPC_TRACER_ON(grpc_polling_trace) &&
-        worker->pollable->root_worker != worker) {
+        worker->pollable_obj->root_worker != worker) {
       gpr_log(GPR_DEBUG, "PS:%p wait %p w=%p for %dms", pollset,
-              worker->pollable, worker,
+              worker->pollable_obj, worker,
               poll_deadline_to_millis_timeout(deadline, *now));
     }
-    while (do_poll && worker->pollable->root_worker != worker) {
-      if (gpr_cv_wait(&worker->cv, &worker->pollable->po.mu, deadline)) {
+    while (do_poll && worker->pollable_obj->root_worker != worker) {
+      if (gpr_cv_wait(&worker->cv, &worker->pollable_obj->po.mu, deadline)) {
         if (GRPC_TRACER_ON(grpc_polling_trace)) {
           gpr_log(GPR_DEBUG, "PS:%p timeout_wait %p w=%p", pollset,
-                  worker->pollable, worker);
+                  worker->pollable_obj, worker);
         }
         do_poll = false;
       } else if (worker->kicked) {
         if (GRPC_TRACER_ON(grpc_polling_trace)) {
-          gpr_log(GPR_DEBUG, "PS:%p wakeup %p w=%p", pollset, worker->pollable,
-                  worker);
+          gpr_log(GPR_DEBUG, "PS:%p wakeup %p w=%p", pollset,
+                  worker->pollable_obj, worker);
         }
         do_poll = false;
       } else if (GRPC_TRACER_ON(grpc_polling_trace) &&
-                 worker->pollable->root_worker != worker) {
+                 worker->pollable_obj->root_worker != worker) {
         gpr_log(GPR_DEBUG, "PS:%p spurious_wakeup %p w=%p", pollset,
-                worker->pollable, worker);
+                worker->pollable_obj, worker);
       }
     }
-    if (worker->pollable != &pollset->pollable) {
-      gpr_mu_unlock(&worker->pollable->po.mu);
-      gpr_mu_lock(&pollset->pollable.po.mu);
-      gpr_mu_lock(&worker->pollable->po.mu);
+    if (worker->pollable_obj != &pollset->pollable_obj) {
+      gpr_mu_unlock(&worker->pollable_obj->po.mu);
+      gpr_mu_lock(&pollset->pollable_obj.po.mu);
+      gpr_mu_lock(&worker->pollable_obj->po.mu);
     }
     *now = gpr_now(now->clock_type);
   }
 
   return do_poll && pollset->shutdown_closure == NULL &&
-         pollset->current_pollable == worker->pollable;
+         pollset->current_pollable == worker->pollable_obj;
 }
 
 static void end_worker(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
                        grpc_pollset_worker *worker,
                        grpc_pollset_worker **worker_hdl) {
   if (NEW_ROOT ==
-      worker_remove(&worker->pollable->root_worker, PWL_POLLABLE, worker)) {
-    gpr_cv_signal(&worker->pollable->root_worker->cv);
+      worker_remove(&worker->pollable_obj->root_worker, PWL_POLLABLE, worker)) {
+    gpr_cv_signal(&worker->pollable_obj->root_worker->cv);
   }
   if (worker->initialized_cv) {
     gpr_cv_destroy(&worker->cv);
   }
-  if (pollset_is_pollable_fd(pollset, worker->pollable)) {
-    UNREF_BY(exec_ctx, (grpc_fd *)worker->pollable, 2, "one_poll");
+  if (pollset_is_pollable_fd(pollset, worker->pollable_obj)) {
+    UNREF_BY(exec_ctx, (grpc_fd *)worker->pollable_obj, 2, "one_poll");
   }
   if (EMPTIED == worker_remove(&pollset->root_worker, PWL_POLLSET, worker)) {
     pollset_maybe_finish_shutdown(exec_ctx, pollset);
@@ -972,41 +976,41 @@ static grpc_error *pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
     pollset->kicked_without_poller = false;
     return GRPC_ERROR_NONE;
   }
-  if (pollset->current_pollable != &pollset->pollable) {
+  if (pollset->current_pollable != &pollset->pollable_obj) {
     gpr_mu_lock(&pollset->current_pollable->po.mu);
   }
   if (begin_worker(pollset, &worker, worker_hdl, &now, deadline)) {
     gpr_tls_set(&g_current_thread_pollset, (intptr_t)pollset);
     gpr_tls_set(&g_current_thread_worker, (intptr_t)&worker);
     GPR_ASSERT(!pollset->shutdown_closure);
-    append_error(&error, pollable_materialize(worker.pollable), err_desc);
-    if (worker.pollable != &pollset->pollable) {
-      gpr_mu_unlock(&worker.pollable->po.mu);
+    append_error(&error, pollable_materialize(worker.pollable_obj), err_desc);
+    if (worker.pollable_obj != &pollset->pollable_obj) {
+      gpr_mu_unlock(&worker.pollable_obj->po.mu);
     }
-    gpr_mu_unlock(&pollset->pollable.po.mu);
+    gpr_mu_unlock(&pollset->pollable_obj.po.mu);
     if (pollset->event_cursor == pollset->event_count) {
-      append_error(&error, pollset_epoll(exec_ctx, pollset, worker.pollable,
+      append_error(&error, pollset_epoll(exec_ctx, pollset, worker.pollable_obj,
                                          now, deadline),
                    err_desc);
     }
     append_error(&error, pollset_process_events(exec_ctx, pollset, false),
                  err_desc);
-    gpr_mu_lock(&pollset->pollable.po.mu);
-    if (worker.pollable != &pollset->pollable) {
-      gpr_mu_lock(&worker.pollable->po.mu);
+    gpr_mu_lock(&pollset->pollable_obj.po.mu);
+    if (worker.pollable_obj != &pollset->pollable_obj) {
+      gpr_mu_lock(&worker.pollable_obj->po.mu);
     }
     gpr_tls_set(&g_current_thread_pollset, 0);
     gpr_tls_set(&g_current_thread_worker, 0);
     pollset_maybe_finish_shutdown(exec_ctx, pollset);
   }
   end_worker(exec_ctx, pollset, &worker, worker_hdl);
-  if (worker.pollable != &pollset->pollable) {
-    gpr_mu_unlock(&worker.pollable->po.mu);
+  if (worker.pollable_obj != &pollset->pollable_obj) {
+    gpr_mu_unlock(&worker.pollable_obj->po.mu);
   }
   if (grpc_exec_ctx_has_work(exec_ctx)) {
-    gpr_mu_unlock(&pollset->pollable.po.mu);
+    gpr_mu_unlock(&pollset->pollable_obj.po.mu);
     grpc_exec_ctx_flush(exec_ctx);
-    gpr_mu_lock(&pollset->pollable.po.mu);
+    gpr_mu_lock(&pollset->pollable_obj.po.mu);
   }
   return error;
 }
@@ -1029,20 +1033,20 @@ static grpc_error *pollset_add_fd_locked(grpc_exec_ctx *exec_ctx,
               "PS:%p add fd %p; transition pollable from empty to fd", pollset,
               fd);
     }
-    /* empty pollable --> single fd pollable_t */
+    /* empty pollable --> single fd pollable */
     pollset_kick_all(exec_ctx, pollset);
-    pollset->current_pollable = &fd->pollable;
-    if (!fd_locked) gpr_mu_lock(&fd->pollable.po.mu);
+    pollset->current_pollable = &fd->pollable_obj;
+    if (!fd_locked) gpr_mu_lock(&fd->pollable_obj.po.mu);
     append_error(&error, fd_become_pollable_locked(fd), err_desc);
-    if (!fd_locked) gpr_mu_unlock(&fd->pollable.po.mu);
+    if (!fd_locked) gpr_mu_unlock(&fd->pollable_obj.po.mu);
     REF_BY(fd, 2, "pollset_pollable");
-  } else if (pollset->current_pollable == &pollset->pollable) {
+  } else if (pollset->current_pollable == &pollset->pollable_obj) {
     if (GRPC_TRACER_ON(grpc_polling_trace)) {
       gpr_log(GPR_DEBUG, "PS:%p add fd %p; already multipolling", pollset, fd);
     }
     append_error(&error, pollable_add_fd(pollset->current_pollable, fd),
                  err_desc);
-  } else if (pollset->current_pollable != &fd->pollable) {
+  } else if (pollset->current_pollable != &fd->pollable_obj) {
     grpc_fd *had_fd = (grpc_fd *)pollset->current_pollable;
     if (GRPC_TRACER_ON(grpc_polling_trace)) {
       gpr_log(GPR_DEBUG,
@@ -1055,11 +1059,11 @@ static grpc_error *pollset_add_fd_locked(grpc_exec_ctx *exec_ctx,
     grpc_lfev_set_ready(exec_ctx, &had_fd->read_closure, "read");
     grpc_lfev_set_ready(exec_ctx, &had_fd->write_closure, "write");
     pollset_kick_all(exec_ctx, pollset);
-    pollset->current_pollable = &pollset->pollable;
-    if (append_error(&error, pollable_materialize(&pollset->pollable),
+    pollset->current_pollable = &pollset->pollable_obj;
+    if (append_error(&error, pollable_materialize(&pollset->pollable_obj),
                      err_desc)) {
-      pollable_add_fd(&pollset->pollable, had_fd);
-      pollable_add_fd(&pollset->pollable, fd);
+      pollable_add_fd(&pollset->pollable_obj, had_fd);
+      pollable_add_fd(&pollset->pollable_obj, fd);
     }
     GRPC_CLOSURE_SCHED(exec_ctx,
                        GRPC_CLOSURE_CREATE(unref_fd_no_longer_poller, had_fd,
@@ -1071,9 +1075,9 @@ static grpc_error *pollset_add_fd_locked(grpc_exec_ctx *exec_ctx,
 
 static void pollset_add_fd(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
                            grpc_fd *fd) {
-  gpr_mu_lock(&pollset->pollable.po.mu);
+  gpr_mu_lock(&pollset->pollable_obj.po.mu);
   grpc_error *error = pollset_add_fd_locked(exec_ctx, pollset, fd, false);
-  gpr_mu_unlock(&pollset->pollable.po.mu);
+  gpr_mu_unlock(&pollset->pollable_obj.po.mu);
   GRPC_LOG_IF_ERROR("pollset_add_fd", error);
 }
 
@@ -1095,7 +1099,7 @@ static void pollset_set_destroy(grpc_exec_ctx *exec_ctx,
 
 static void pollset_set_add_fd(grpc_exec_ctx *exec_ctx, grpc_pollset_set *pss,
                                grpc_fd *fd) {
-  po_join(exec_ctx, &pss->po, &fd->pollable.po);
+  po_join(exec_ctx, &pss->po, &fd->pollable_obj.po);
 }
 
 static void pollset_set_del_fd(grpc_exec_ctx *exec_ctx, grpc_pollset_set *pss,
@@ -1103,7 +1107,7 @@ static void pollset_set_del_fd(grpc_exec_ctx *exec_ctx, grpc_pollset_set *pss,
 
 static void pollset_set_add_pollset(grpc_exec_ctx *exec_ctx,
                                     grpc_pollset_set *pss, grpc_pollset *ps) {
-  po_join(exec_ctx, &pss->po, &ps->pollable.po);
+  po_join(exec_ctx, &pss->po, &ps->pollable_obj.po);
 }
 
 static void pollset_set_del_pollset(grpc_exec_ctx *exec_ctx,
diff --git a/src/core/lib/surface/call.c b/src/core/lib/surface/call.c
index de5aa7b6bec..e258719c4da 100644
--- a/src/core/lib/surface/call.c
+++ b/src/core/lib/surface/call.c
@@ -135,7 +135,7 @@ typedef struct batch_control {
 typedef struct {
   gpr_mu child_list_mu;
   grpc_call *first_child;
-} parent_call_t;
+} parent_call;
 
 typedef struct {
   grpc_call *parent;
@@ -144,7 +144,7 @@ typedef struct {
       parent->mu */
   grpc_call *sibling_next;
   grpc_call *sibling_prev;
-} child_call_t;
+} child_call;
 
 #define RECV_NONE ((gpr_atm)0)
 #define RECV_INITIAL_METADATA_FIRST ((gpr_atm)1)
@@ -157,8 +157,8 @@ struct grpc_call {
   grpc_polling_entity pollent;
   grpc_channel *channel;
   gpr_timespec start_time;
-  /* parent_call_t* */ gpr_atm parent_call_atm;
-  child_call_t *child_call;
+  /* parent_call* */ gpr_atm parent_call_atm;
+  child_call *child;
 
   /* client or server call */
   bool is_client;
@@ -304,21 +304,21 @@ void *grpc_call_arena_alloc(grpc_call *call, size_t size) {
   return gpr_arena_alloc(call->arena, size);
 }
 
-static parent_call_t *get_or_create_parent_call(grpc_call *call) {
-  parent_call_t *p = (parent_call_t *)gpr_atm_acq_load(&call->parent_call_atm);
+static parent_call *get_or_create_parent_call(grpc_call *call) {
+  parent_call *p = (parent_call *)gpr_atm_acq_load(&call->parent_call_atm);
   if (p == NULL) {
-    p = (parent_call_t *)gpr_arena_alloc(call->arena, sizeof(*p));
+    p = (parent_call *)gpr_arena_alloc(call->arena, sizeof(*p));
     gpr_mu_init(&p->child_list_mu);
     if (!gpr_atm_rel_cas(&call->parent_call_atm, (gpr_atm)NULL, (gpr_atm)p)) {
       gpr_mu_destroy(&p->child_list_mu);
-      p = (parent_call_t *)gpr_atm_acq_load(&call->parent_call_atm);
+      p = (parent_call *)gpr_atm_acq_load(&call->parent_call_atm);
     }
   }
   return p;
 }
 
-static parent_call_t *get_parent_call(grpc_call *call) {
-  return (parent_call_t *)gpr_atm_acq_load(&call->parent_call_atm);
+static parent_call *get_parent_call(grpc_call *call) {
+  return (parent_call *)gpr_atm_acq_load(&call->parent_call_atm);
 }
 
 grpc_error *grpc_call_create(grpc_exec_ctx *exec_ctx,
@@ -377,24 +377,24 @@ grpc_error *grpc_call_create(grpc_exec_ctx *exec_ctx,
 
   bool immediately_cancel = false;
 
-  if (args->parent_call != NULL) {
-    child_call_t *cc = call->child_call =
-        (child_call_t *)gpr_arena_alloc(arena, sizeof(child_call_t));
-    call->child_call->parent = args->parent_call;
+  if (args->parent != NULL) {
+    child_call *cc = call->child =
+        (child_call *)gpr_arena_alloc(arena, sizeof(child_call));
+    call->child->parent = args->parent;
 
-    GRPC_CALL_INTERNAL_REF(args->parent_call, "child");
+    GRPC_CALL_INTERNAL_REF(args->parent, "child");
     GPR_ASSERT(call->is_client);
-    GPR_ASSERT(!args->parent_call->is_client);
+    GPR_ASSERT(!args->parent->is_client);
 
-    parent_call_t *pc = get_or_create_parent_call(args->parent_call);
+    parent_call *pc = get_or_create_parent_call(args->parent);
 
     gpr_mu_lock(&pc->child_list_mu);
 
     if (args->propagation_mask & GRPC_PROPAGATE_DEADLINE) {
       send_deadline = gpr_time_min(
           gpr_convert_clock_type(send_deadline,
-                                 args->parent_call->send_deadline.clock_type),
-          args->parent_call->send_deadline);
+                                 args->parent->send_deadline.clock_type),
+          args->parent->send_deadline);
     }
     /* for now GRPC_PROPAGATE_TRACING_CONTEXT *MUST* be passed with
      * GRPC_PROPAGATE_STATS_CONTEXT */
@@ -406,9 +406,9 @@ grpc_error *grpc_call_create(grpc_exec_ctx *exec_ctx,
                                    "Census tracing propagation requested "
                                    "without Census context propagation"));
       }
-      grpc_call_context_set(
-          call, GRPC_CONTEXT_TRACING,
-          args->parent_call->context[GRPC_CONTEXT_TRACING].value, NULL);
+      grpc_call_context_set(call, GRPC_CONTEXT_TRACING,
+                            args->parent->context[GRPC_CONTEXT_TRACING].value,
+                            NULL);
     } else if (args->propagation_mask & GRPC_PROPAGATE_CENSUS_STATS_CONTEXT) {
       add_init_error(&error, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
                                  "Census context propagation requested "
@@ -416,7 +416,7 @@ grpc_error *grpc_call_create(grpc_exec_ctx *exec_ctx,
     }
     if (args->propagation_mask & GRPC_PROPAGATE_CANCELLATION) {
       call->cancellation_is_inherited = 1;
-      if (gpr_atm_acq_load(&args->parent_call->received_final_op_atm)) {
+      if (gpr_atm_acq_load(&args->parent->received_final_op_atm)) {
         immediately_cancel = true;
       }
     }
@@ -426,9 +426,9 @@ grpc_error *grpc_call_create(grpc_exec_ctx *exec_ctx,
       cc->sibling_next = cc->sibling_prev = call;
     } else {
       cc->sibling_next = pc->first_child;
-      cc->sibling_prev = pc->first_child->child_call->sibling_prev;
-      cc->sibling_next->child_call->sibling_prev =
-          cc->sibling_prev->child_call->sibling_next = call;
+      cc->sibling_prev = pc->first_child->child->sibling_prev;
+      cc->sibling_next->child->sibling_prev =
+          cc->sibling_prev->child->sibling_next = call;
     }
 
     gpr_mu_unlock(&pc->child_list_mu);
@@ -533,7 +533,7 @@ static void destroy_call(grpc_exec_ctx *exec_ctx, void *call,
   if (c->receiving_stream != NULL) {
     grpc_byte_stream_destroy(exec_ctx, c->receiving_stream);
   }
-  parent_call_t *pc = get_parent_call(c);
+  parent_call *pc = get_parent_call(c);
   if (pc != NULL) {
     gpr_mu_destroy(&pc->child_list_mu);
   }
@@ -570,14 +570,14 @@ void grpc_call_ref(grpc_call *c) { gpr_ref(&c->ext_ref); }
 void grpc_call_unref(grpc_call *c) {
   if (!gpr_unref(&c->ext_ref)) return;
 
-  child_call_t *cc = c->child_call;
+  child_call *cc = c->child;
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
 
   GPR_TIMER_BEGIN("grpc_call_unref", 0);
   GRPC_API_TRACE("grpc_call_unref(c=%p)", 1, (c));
 
   if (cc) {
-    parent_call_t *pc = get_parent_call(cc->parent);
+    parent_call *pc = get_parent_call(cc->parent);
     gpr_mu_lock(&pc->child_list_mu);
     if (c == pc->first_child) {
       pc->first_child = cc->sibling_next;
@@ -585,8 +585,8 @@ void grpc_call_unref(grpc_call *c) {
         pc->first_child = NULL;
       }
     }
-    cc->sibling_prev->child_call->sibling_next = cc->sibling_next;
-    cc->sibling_next->child_call->sibling_prev = cc->sibling_prev;
+    cc->sibling_prev->child->sibling_next = cc->sibling_next;
+    cc->sibling_next->child->sibling_prev = cc->sibling_prev;
     gpr_mu_unlock(&pc->child_list_mu);
     GRPC_CALL_INTERNAL_UNREF(&exec_ctx, cc->parent, "child");
   }
@@ -1309,14 +1309,14 @@ static void post_batch_completion(grpc_exec_ctx *exec_ctx,
 
     /* propagate cancellation to any interested children */
     gpr_atm_rel_store(&call->received_final_op_atm, 1);
-    parent_call_t *pc = get_parent_call(call);
+    parent_call *pc = get_parent_call(call);
     if (pc != NULL) {
       grpc_call *child;
       gpr_mu_lock(&pc->child_list_mu);
       child = pc->first_child;
       if (child != NULL) {
         do {
-          next_child_call = child->child_call->sibling_next;
+          next_child_call = child->child->sibling_next;
           if (child->cancellation_is_inherited) {
             GRPC_CALL_INTERNAL_REF(child, "propagate_cancel");
             cancel_with_error(exec_ctx, child, STATUS_FROM_API_OVERRIDE,
diff --git a/src/core/lib/surface/call.h b/src/core/lib/surface/call.h
index d537637cbb8..c680139cf68 100644
--- a/src/core/lib/surface/call.h
+++ b/src/core/lib/surface/call.h
@@ -37,7 +37,7 @@ typedef void (*grpc_ioreq_completion_func)(grpc_exec_ctx *exec_ctx,
 typedef struct grpc_call_create_args {
   grpc_channel *channel;
 
-  grpc_call *parent_call;
+  grpc_call *parent;
   uint32_t propagation_mask;
 
   grpc_completion_queue *cq;
diff --git a/src/core/lib/surface/channel.c b/src/core/lib/surface/channel.c
index 2f9b677c85e..48962e5e455 100644
--- a/src/core/lib/surface/channel.c
+++ b/src/core/lib/surface/channel.c
@@ -282,7 +282,7 @@ static grpc_call *grpc_channel_create_call_internal(
   grpc_call_create_args args;
   memset(&args, 0, sizeof(args));
   args.channel = channel;
-  args.parent_call = parent_call;
+  args.parent = parent_call;
   args.propagation_mask = propagation_mask;
   args.cq = cq;
   args.pollset_set_alternative = pollset_set_alternative;

From 8f798e9ca153f844033ce49f261eeb345bd09c4f Mon Sep 17 00:00:00 2001
From: Yash Tibrewal <yashkt@google.com>
Date: Wed, 13 Sep 2017 15:45:47 -0700
Subject: [PATCH 10/20] %s/current_pollable/current_pollable_obj

---
 src/core/lib/iomgr/ev_epollex_linux.c | 32 +++++++++++++--------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/src/core/lib/iomgr/ev_epollex_linux.c b/src/core/lib/iomgr/ev_epollex_linux.c
index 9934f8d3299..51200fc0643 100644
--- a/src/core/lib/iomgr/ev_epollex_linux.c
+++ b/src/core/lib/iomgr/ev_epollex_linux.c
@@ -201,7 +201,7 @@ struct grpc_pollset_worker {
 
 struct grpc_pollset {
   pollable pollable_obj;
-  pollable *current_pollable;
+  pollable *current_pollable_obj;
   int kick_alls_pending;
   bool kicked_without_poller;
   grpc_closure *shutdown_closure;
@@ -667,7 +667,7 @@ static grpc_error *pollset_kick_inner(grpc_pollset *pollset, pollable *p,
 /* p->po.mu must be held before calling this function */
 static grpc_error *pollset_kick(grpc_pollset *pollset,
                                 grpc_pollset_worker *specific_worker) {
-  pollable *p = pollset->current_pollable;
+  pollable *p = pollset->current_pollable_obj;
   if (p != &pollset->pollable_obj) {
     gpr_mu_lock(&p->po.mu);
   }
@@ -680,7 +680,7 @@ static grpc_error *pollset_kick(grpc_pollset *pollset,
 
 static void pollset_init(grpc_pollset *pollset, gpr_mu **mu) {
   pollable_init(&pollset->pollable_obj, PO_POLLSET);
-  pollset->current_pollable = &g_empty_pollable;
+  pollset->current_pollable_obj = &g_empty_pollable;
   pollset->kicked_without_poller = false;
   pollset->shutdown_closure = NULL;
   pollset->root_worker = NULL;
@@ -795,8 +795,8 @@ static grpc_error *pollset_process_events(grpc_exec_ctx *exec_ctx,
 /* pollset_shutdown is guaranteed to be called before pollset_destroy. */
 static void pollset_destroy(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) {
   pollable_destroy(&pollset->pollable_obj);
-  if (pollset_is_pollable_fd(pollset, pollset->current_pollable)) {
-    UNREF_BY(exec_ctx, (grpc_fd *)pollset->current_pollable, 2,
+  if (pollset_is_pollable_fd(pollset, pollset->current_pollable_obj)) {
+    UNREF_BY(exec_ctx, (grpc_fd *)pollset->current_pollable_obj, 2,
              "pollset_pollable");
   }
   GRPC_LOG_IF_ERROR("pollset_process_events",
@@ -886,7 +886,7 @@ static bool begin_worker(grpc_pollset *pollset, grpc_pollset_worker *worker,
   worker->initialized_cv = false;
   worker->kicked = false;
   worker->pollset = pollset;
-  worker->pollable_obj = pollset->current_pollable;
+  worker->pollable_obj = pollset->current_pollable_obj;
 
   if (pollset_is_pollable_fd(pollset, worker->pollable_obj)) {
     REF_BY((grpc_fd *)worker->pollable_obj, 2, "one_poll");
@@ -934,7 +934,7 @@ static bool begin_worker(grpc_pollset *pollset, grpc_pollset_worker *worker,
   }
 
   return do_poll && pollset->shutdown_closure == NULL &&
-         pollset->current_pollable == worker->pollable_obj;
+         pollset->current_pollable_obj == worker->pollable_obj;
 }
 
 static void end_worker(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
@@ -976,8 +976,8 @@ static grpc_error *pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
     pollset->kicked_without_poller = false;
     return GRPC_ERROR_NONE;
   }
-  if (pollset->current_pollable != &pollset->pollable_obj) {
-    gpr_mu_lock(&pollset->current_pollable->po.mu);
+  if (pollset->current_pollable_obj != &pollset->pollable_obj) {
+    gpr_mu_lock(&pollset->current_pollable_obj->po.mu);
   }
   if (begin_worker(pollset, &worker, worker_hdl, &now, deadline)) {
     gpr_tls_set(&g_current_thread_pollset, (intptr_t)pollset);
@@ -1027,7 +1027,7 @@ static grpc_error *pollset_add_fd_locked(grpc_exec_ctx *exec_ctx,
                                          bool fd_locked) {
   static const char *err_desc = "pollset_add_fd";
   grpc_error *error = GRPC_ERROR_NONE;
-  if (pollset->current_pollable == &g_empty_pollable) {
+  if (pollset->current_pollable_obj == &g_empty_pollable) {
     if (GRPC_TRACER_ON(grpc_polling_trace)) {
       gpr_log(GPR_DEBUG,
               "PS:%p add fd %p; transition pollable from empty to fd", pollset,
@@ -1035,19 +1035,19 @@ static grpc_error *pollset_add_fd_locked(grpc_exec_ctx *exec_ctx,
     }
     /* empty pollable --> single fd pollable */
     pollset_kick_all(exec_ctx, pollset);
-    pollset->current_pollable = &fd->pollable_obj;
+    pollset->current_pollable_obj = &fd->pollable_obj;
     if (!fd_locked) gpr_mu_lock(&fd->pollable_obj.po.mu);
     append_error(&error, fd_become_pollable_locked(fd), err_desc);
     if (!fd_locked) gpr_mu_unlock(&fd->pollable_obj.po.mu);
     REF_BY(fd, 2, "pollset_pollable");
-  } else if (pollset->current_pollable == &pollset->pollable_obj) {
+  } else if (pollset->current_pollable_obj == &pollset->pollable_obj) {
     if (GRPC_TRACER_ON(grpc_polling_trace)) {
       gpr_log(GPR_DEBUG, "PS:%p add fd %p; already multipolling", pollset, fd);
     }
-    append_error(&error, pollable_add_fd(pollset->current_pollable, fd),
+    append_error(&error, pollable_add_fd(pollset->current_pollable_obj, fd),
                  err_desc);
-  } else if (pollset->current_pollable != &fd->pollable_obj) {
-    grpc_fd *had_fd = (grpc_fd *)pollset->current_pollable;
+  } else if (pollset->current_pollable_obj != &fd->pollable_obj) {
+    grpc_fd *had_fd = (grpc_fd *)pollset->current_pollable_obj;
     if (GRPC_TRACER_ON(grpc_polling_trace)) {
       gpr_log(GPR_DEBUG,
               "PS:%p add fd %p; transition pollable from fd %p to multipoller",
@@ -1059,7 +1059,7 @@ static grpc_error *pollset_add_fd_locked(grpc_exec_ctx *exec_ctx,
     grpc_lfev_set_ready(exec_ctx, &had_fd->read_closure, "read");
     grpc_lfev_set_ready(exec_ctx, &had_fd->write_closure, "write");
     pollset_kick_all(exec_ctx, pollset);
-    pollset->current_pollable = &pollset->pollable_obj;
+    pollset->current_pollable_obj = &pollset->pollable_obj;
     if (append_error(&error, pollable_materialize(&pollset->pollable_obj),
                      err_desc)) {
       pollable_add_fd(&pollset->pollable_obj, had_fd);

From 989466171296e296867a3009f615a90d46acf28d Mon Sep 17 00:00:00 2001
From: Muxi Yan <mxyan@google.com>
Date: Thu, 14 Sep 2017 15:21:16 -0700
Subject: [PATCH 11/20] Polish comment

---
 src/objective-c/GRPCClient/GRPCCall.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/objective-c/GRPCClient/GRPCCall.h b/src/objective-c/GRPCClient/GRPCCall.h
index 3b0ef56c3af..df563ca36cf 100644
--- a/src/objective-c/GRPCClient/GRPCCall.h
+++ b/src/objective-c/GRPCClient/GRPCCall.h
@@ -170,9 +170,9 @@ extern id const kGRPCTrailersKey;
 @property (atomic, copy, readwrite) NSString *serverName;
 
 /**
- * The timeout for the RPC call in milliseconds. If set to 0, the call will not timeout. If set to
- * positive, the gRPC call returns with status GRPCErrorCodeDeadlineExceeded. A negative value is
- * not allowed.
+ * The timeout for the RPC call in seconds. If set to 0, the call will not timeout. If set to
+ * positive, the gRPC call returns with status GRPCErrorCodeDeadlineExceeded if it is not completed
+ * within \a timeout seconds. A negative value is not allowed.
  */
 @property NSTimeInterval timeout;
 

From 4b047a3bff92ff377205be38d9044b9d99e06fbb Mon Sep 17 00:00:00 2001
From: Vijay Pai <vpai@google.com>
Date: Mon, 21 Aug 2017 22:34:37 -0700
Subject: [PATCH 12/20] Construction of streams shouldn't require triggering
 async ops

---
 .../cpp/helloworld/greeter_async_client.cc    |  12 +-
 .../cpp/helloworld/greeter_async_client2.cc   |  14 +-
 include/grpc++/generic/generic_stub.h         |   7 +
 include/grpc++/impl/codegen/async_stream.h    | 136 +++--
 .../grpc++/impl/codegen/async_unary_call.h    |  41 +-
 src/compiler/cpp_generator.cc                 | 578 +++++++++++-------
 src/cpp/client/generic_stub.cc                |  23 +-
 test/cpp/codegen/compiler_test_golden         |  40 ++
 test/cpp/codegen/compiler_test_mock_golden    |   5 +
 test/cpp/qps/client_async.cc                  | 153 ++---
 10 files changed, 651 insertions(+), 358 deletions(-)

diff --git a/examples/cpp/helloworld/greeter_async_client.cc b/examples/cpp/helloworld/greeter_async_client.cc
index 64da044ea6f..ddf6c1aaf3d 100644
--- a/examples/cpp/helloworld/greeter_async_client.cc
+++ b/examples/cpp/helloworld/greeter_async_client.cc
@@ -60,11 +60,15 @@ class GreeterClient {
     // Storage for the status of the RPC upon completion.
     Status status;
 
-    // stub_->AsyncSayHello() performs the RPC call, returning an instance we
-    // store in "rpc". Because we are using the asynchronous API, we need to
-    // hold on to the "rpc" instance in order to get updates on the ongoing RPC.
+    // stub_->PrepareAsyncSayHello() creates an RPC object, returning
+    // an instance to store in "call" but does not actually start the RPC
+    // Because we are using the asynchronous API, we need to hold on to
+    // the "call" instance in order to get updates on the ongoing RPC.
     std::unique_ptr<ClientAsyncResponseReader<HelloReply> > rpc(
-        stub_->AsyncSayHello(&context, request, &cq));
+        stub_->PrepareAsyncSayHello(&context, request, &cq));
+
+    // StartCall initiates the RPC call
+    rpc->StartCall();
 
     // Request that, upon completion of the RPC, "reply" be updated with the
     // server's response; "status" with the indication of whether the operation
diff --git a/examples/cpp/helloworld/greeter_async_client2.cc b/examples/cpp/helloworld/greeter_async_client2.cc
index 4192546beff..3154e84d854 100644
--- a/examples/cpp/helloworld/greeter_async_client2.cc
+++ b/examples/cpp/helloworld/greeter_async_client2.cc
@@ -49,11 +49,15 @@ class GreeterClient {
         // Call object to store rpc data
         AsyncClientCall* call = new AsyncClientCall;
 
-        // stub_->AsyncSayHello() performs the RPC call, returning an instance to
-        // store in "call". Because we are using the asynchronous API, we need to
-        // hold on to the "call" instance in order to get updates on the ongoing RPC.
-        call->response_reader = stub_->AsyncSayHello(&call->context, request, &cq_);
-
+        // stub_->PrepareAsyncSayHello() creates an RPC object, returning
+        // an instance to store in "call" but does not actually start the RPC
+        // Because we are using the asynchronous API, we need to hold on to
+        // the "call" instance in order to get updates on the ongoing RPC.
+        call->response_reader =
+            stub_->PrepareAsyncSayHello(&call->context, request, &cq_);
+
+        // StartCall initiates the RPC call
+        call->response_reader->StartCall();
 
         // Request that, upon completion of the RPC, "reply" be updated with the
         // server's response; "status" with the indication of whether the operation
diff --git a/include/grpc++/generic/generic_stub.h b/include/grpc++/generic/generic_stub.h
index 7b269d0887a..2b3ff59ea24 100644
--- a/include/grpc++/generic/generic_stub.h
+++ b/include/grpc++/generic/generic_stub.h
@@ -44,6 +44,13 @@ class GenericStub final {
       ClientContext* context, const grpc::string& method, CompletionQueue* cq,
       void* tag);
 
+  /// Setup a call to a named method \a method using \a context, but don't
+  /// start it. Let it be started explicitly with StartCall and a tag.
+  /// The return value only indicates whether or not registration of the call
+  /// succeeded (i.e. the call won't proceed if the return value is nullptr).
+  std::unique_ptr<GenericClientAsyncReaderWriter> PrepareCall(
+      ClientContext* context, const grpc::string& method, CompletionQueue* cq);
+
  private:
   std::shared_ptr<ChannelInterface> channel_;
 };
diff --git a/include/grpc++/impl/codegen/async_stream.h b/include/grpc++/impl/codegen/async_stream.h
index 9cf7ac30ddf..e60572fc939 100644
--- a/include/grpc++/impl/codegen/async_stream.h
+++ b/include/grpc++/impl/codegen/async_stream.h
@@ -35,6 +35,11 @@ class ClientAsyncStreamingInterface {
  public:
   virtual ~ClientAsyncStreamingInterface() {}
 
+  /// Start the call that was set up by the constructor, but only if the
+  /// constructor was invoked through the "Prepare" API which doesn't actually
+  /// start the call
+  virtual void StartCall(void* tag) = 0;
+
   /// Request notification of the reading of the initial metadata. Completion
   /// will be notified by \a tag on the associated completion queue.
   /// This call is optional, but if it is used, it cannot be used concurrently
@@ -156,20 +161,22 @@ class ClientAsyncReaderInterface : public ClientAsyncStreamingInterface,
 template <class R>
 class ClientAsyncReader final : public ClientAsyncReaderInterface<R> {
  public:
-  /// Create a stream and write the first request out.
+  /// Create a stream object.
+  /// Write the first request out if \a start is set.
   /// \a tag will be notified on \a cq when the call has been started and
-  /// \a request has been written out.
+  /// \a request has been written out. If \a start is not set, \a tag must be
+  /// nullptr and the actual call must be initiated by StartCall
   /// Note that \a context will be used to fill in custom initial metadata
   /// used to send to the server when starting the call.
   template <class W>
   static ClientAsyncReader* Create(ChannelInterface* channel,
                                    CompletionQueue* cq, const RpcMethod& method,
                                    ClientContext* context, const W& request,
-                                   void* tag) {
+                                   bool start, void* tag) {
     Call call = channel->CreateCall(method, context, cq);
     return new (g_core_codegen_interface->grpc_call_arena_alloc(
         call.call(), sizeof(ClientAsyncReader)))
-        ClientAsyncReader(call, context, request, tag);
+        ClientAsyncReader(call, context, request, start, tag);
   }
 
   // always allocated against a call arena, no memory free required
@@ -177,6 +184,12 @@ class ClientAsyncReader final : public ClientAsyncReaderInterface<R> {
     assert(size == sizeof(ClientAsyncReader));
   }
 
+  void StartCall(void* tag) override {
+    assert(!started_);
+    started_ = true;
+    StartCallInternal(tag);
+  }
+
   /// See the \a ClientAsyncStreamingInterface.ReadInitialMetadata
   /// method for semantics.
   ///
@@ -186,6 +199,7 @@ class ClientAsyncReader final : public ClientAsyncReaderInterface<R> {
   ///     calling code can access the received metadata through the
   ///     \a ClientContext.
   void ReadInitialMetadata(void* tag) override {
+    assert(started_);
     GPR_CODEGEN_ASSERT(!context_->initial_metadata_received_);
 
     meta_ops_.set_output_tag(tag);
@@ -194,6 +208,7 @@ class ClientAsyncReader final : public ClientAsyncReaderInterface<R> {
   }
 
   void Read(R* msg, void* tag) override {
+    assert(started_);
     read_ops_.set_output_tag(tag);
     if (!context_->initial_metadata_received_) {
       read_ops_.RecvInitialMetadata(context_);
@@ -208,6 +223,7 @@ class ClientAsyncReader final : public ClientAsyncReaderInterface<R> {
   ///   - the \a ClientContext associated with this call is updated with
   ///     possible initial and trailing metadata received from the server.
   void Finish(Status* status, void* tag) override {
+    assert(started_);
     finish_ops_.set_output_tag(tag);
     if (!context_->initial_metadata_received_) {
       finish_ops_.RecvInitialMetadata(context_);
@@ -219,19 +235,28 @@ class ClientAsyncReader final : public ClientAsyncReaderInterface<R> {
  private:
   template <class W>
   ClientAsyncReader(Call call, ClientContext* context, const W& request,
-                    void* tag)
-      : context_(context), call_(call) {
-    init_ops_.set_output_tag(tag);
-    init_ops_.SendInitialMetadata(context->send_initial_metadata_,
-                                  context->initial_metadata_flags());
+                    bool start, void* tag)
+      : context_(context), call_(call), started_(start) {
     // TODO(ctiller): don't assert
     GPR_CODEGEN_ASSERT(init_ops_.SendMessage(request).ok());
     init_ops_.ClientSendClose();
+    if (start) {
+      StartCallInternal(tag);
+    } else {
+      assert(tag == nullptr);
+    }
+  }
+
+  void StartCallInternal(void* tag) {
+    init_ops_.SendInitialMetadata(context_->send_initial_metadata_,
+                                  context_->initial_metadata_flags());
+    init_ops_.set_output_tag(tag);
     call_.PerformOps(&init_ops_);
   }
 
   ClientContext* context_;
   Call call_;
+  bool started_;
   CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage, CallOpClientSendClose>
       init_ops_;
   CallOpSet<CallOpRecvInitialMetadata> meta_ops_;
@@ -257,9 +282,12 @@ class ClientAsyncWriterInterface : public ClientAsyncStreamingInterface,
 template <class W>
 class ClientAsyncWriter final : public ClientAsyncWriterInterface<W> {
  public:
-  /// Create a stream and write the first request out.
+  /// Create a stream object.
+  /// Start the RPC if \a start is set
   /// \a tag will be notified on \a cq when the call has been started (i.e.
   /// intitial metadata sent) and \a request has been written out.
+  /// If \a start is not set, \a tag must be nullptr and the actual call
+  /// must be initiated by StartCall
   /// Note that \a context will be used to fill in custom initial metadata
   /// used to send to the server when starting the call.
   /// \a response will be filled in with the single expected response
@@ -269,11 +297,11 @@ class ClientAsyncWriter final : public ClientAsyncWriterInterface<W> {
   static ClientAsyncWriter* Create(ChannelInterface* channel,
                                    CompletionQueue* cq, const RpcMethod& method,
                                    ClientContext* context, R* response,
-                                   void* tag) {
+                                   bool start, void* tag) {
     Call call = channel->CreateCall(method, context, cq);
     return new (g_core_codegen_interface->grpc_call_arena_alloc(
         call.call(), sizeof(ClientAsyncWriter)))
-        ClientAsyncWriter(call, context, response, tag);
+        ClientAsyncWriter(call, context, response, start, tag);
   }
 
   // always allocated against a call arena, no memory free required
@@ -281,6 +309,12 @@ class ClientAsyncWriter final : public ClientAsyncWriterInterface<W> {
     assert(size == sizeof(ClientAsyncWriter));
   }
 
+  void StartCall(void* tag) override {
+    assert(!started_);
+    started_ = true;
+    StartCallInternal(tag);
+  }
+
   /// See the \a ClientAsyncStreamingInterface.ReadInitialMetadata method for
   /// semantics.
   ///
@@ -289,6 +323,7 @@ class ClientAsyncWriter final : public ClientAsyncWriterInterface<W> {
   ///     associated with this call is updated, and the calling code can access
   ///     the received metadata through the \a ClientContext.
   void ReadInitialMetadata(void* tag) override {
+    assert(started_);
     GPR_CODEGEN_ASSERT(!context_->initial_metadata_received_);
 
     meta_ops_.set_output_tag(tag);
@@ -297,6 +332,7 @@ class ClientAsyncWriter final : public ClientAsyncWriterInterface<W> {
   }
 
   void Write(const W& msg, void* tag) override {
+    assert(started_);
     write_ops_.set_output_tag(tag);
     // TODO(ctiller): don't assert
     GPR_CODEGEN_ASSERT(write_ops_.SendMessage(msg).ok());
@@ -304,6 +340,7 @@ class ClientAsyncWriter final : public ClientAsyncWriterInterface<W> {
   }
 
   void Write(const W& msg, WriteOptions options, void* tag) override {
+    assert(started_);
     write_ops_.set_output_tag(tag);
     if (options.is_last_message()) {
       options.set_buffer_hint();
@@ -315,6 +352,7 @@ class ClientAsyncWriter final : public ClientAsyncWriterInterface<W> {
   }
 
   void WritesDone(void* tag) override {
+    assert(started_);
     write_ops_.set_output_tag(tag);
     write_ops_.ClientSendClose();
     call_.PerformOps(&write_ops_);
@@ -328,6 +366,7 @@ class ClientAsyncWriter final : public ClientAsyncWriterInterface<W> {
   ///   - attempts to fill in the \a response parameter passed to this class's
   ///     constructor with the server's response message.
   void Finish(Status* status, void* tag) override {
+    assert(started_);
     finish_ops_.set_output_tag(tag);
     if (!context_->initial_metadata_received_) {
       finish_ops_.RecvInitialMetadata(context_);
@@ -338,25 +377,32 @@ class ClientAsyncWriter final : public ClientAsyncWriterInterface<W> {
 
  private:
   template <class R>
-  ClientAsyncWriter(Call call, ClientContext* context, R* response, void* tag)
-      : context_(context), call_(call) {
+  ClientAsyncWriter(Call call, ClientContext* context, R* response, bool start,
+                    void* tag)
+      : context_(context), call_(call), started_(start) {
     finish_ops_.RecvMessage(response);
     finish_ops_.AllowNoMessage();
-    // if corked bit is set in context, we buffer up the initial metadata to
-    // coalesce with later message to be sent. No op is performed.
-    if (context_->initial_metadata_corked_) {
-      write_ops_.SendInitialMetadata(context->send_initial_metadata_,
-                                     context->initial_metadata_flags());
+    if (start) {
+      StartCallInternal(tag);
     } else {
+      assert(tag == nullptr);
+    }
+  }
+
+  void StartCallInternal(void* tag) {
+    write_ops_.SendInitialMetadata(context_->send_initial_metadata_,
+                                   context_->initial_metadata_flags());
+    // if corked bit is set in context, we just keep the initial metadata
+    // buffered up to coalesce with later message send. No op is performed.
+    if (!context_->initial_metadata_corked_) {
       write_ops_.set_output_tag(tag);
-      write_ops_.SendInitialMetadata(context->send_initial_metadata_,
-                                     context->initial_metadata_flags());
       call_.PerformOps(&write_ops_);
     }
   }
 
   ClientContext* context_;
   Call call_;
+  bool started_;
   CallOpSet<CallOpRecvInitialMetadata> meta_ops_;
   CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage, CallOpClientSendClose>
       write_ops_;
@@ -388,20 +434,23 @@ template <class W, class R>
 class ClientAsyncReaderWriter final
     : public ClientAsyncReaderWriterInterface<W, R> {
  public:
-  /// Create a stream and write the first request out.
+  /// Create a stream object.
+  /// Start the RPC request if \a start is set.
   /// \a tag will be notified on \a cq when the call has been started (i.e.
-  /// intitial metadata sent).
+  /// intitial metadata sent). If \a start is not set, \a tag must be
+  /// nullptr and the actual call must be initiated by StartCall
   /// Note that \a context will be used to fill in custom initial metadata
   /// used to send to the server when starting the call.
   static ClientAsyncReaderWriter* Create(ChannelInterface* channel,
                                          CompletionQueue* cq,
                                          const RpcMethod& method,
-                                         ClientContext* context, void* tag) {
+                                         ClientContext* context, bool start,
+                                         void* tag) {
     Call call = channel->CreateCall(method, context, cq);
 
     return new (g_core_codegen_interface->grpc_call_arena_alloc(
         call.call(), sizeof(ClientAsyncReaderWriter)))
-        ClientAsyncReaderWriter(call, context, tag);
+        ClientAsyncReaderWriter(call, context, start, tag);
   }
 
   // always allocated against a call arena, no memory free required
@@ -409,6 +458,12 @@ class ClientAsyncReaderWriter final
     assert(size == sizeof(ClientAsyncReaderWriter));
   }
 
+  void StartCall(void* tag) override {
+    assert(!started_);
+    started_ = true;
+    StartCallInternal(tag);
+  }
+
   /// See the \a ClientAsyncStreamingInterface.ReadInitialMetadata method
   /// for semantics of this method.
   ///
@@ -417,6 +472,7 @@ class ClientAsyncReaderWriter final
   ///     is updated with it, and then the receiving initial metadata can
   ///     be accessed through this \a ClientContext.
   void ReadInitialMetadata(void* tag) override {
+    assert(started_);
     GPR_CODEGEN_ASSERT(!context_->initial_metadata_received_);
 
     meta_ops_.set_output_tag(tag);
@@ -425,6 +481,7 @@ class ClientAsyncReaderWriter final
   }
 
   void Read(R* msg, void* tag) override {
+    assert(started_);
     read_ops_.set_output_tag(tag);
     if (!context_->initial_metadata_received_) {
       read_ops_.RecvInitialMetadata(context_);
@@ -434,6 +491,7 @@ class ClientAsyncReaderWriter final
   }
 
   void Write(const W& msg, void* tag) override {
+    assert(started_);
     write_ops_.set_output_tag(tag);
     // TODO(ctiller): don't assert
     GPR_CODEGEN_ASSERT(write_ops_.SendMessage(msg).ok());
@@ -441,6 +499,7 @@ class ClientAsyncReaderWriter final
   }
 
   void Write(const W& msg, WriteOptions options, void* tag) override {
+    assert(started_);
     write_ops_.set_output_tag(tag);
     if (options.is_last_message()) {
       options.set_buffer_hint();
@@ -452,6 +511,7 @@ class ClientAsyncReaderWriter final
   }
 
   void WritesDone(void* tag) override {
+    assert(started_);
     write_ops_.set_output_tag(tag);
     write_ops_.ClientSendClose();
     call_.PerformOps(&write_ops_);
@@ -462,6 +522,7 @@ class ClientAsyncReaderWriter final
   ///   - the \a ClientContext associated with this call is updated with
   ///     possible initial and trailing metadata sent from the server.
   void Finish(Status* status, void* tag) override {
+    assert(started_);
     finish_ops_.set_output_tag(tag);
     if (!context_->initial_metadata_received_) {
       finish_ops_.RecvInitialMetadata(context_);
@@ -471,23 +532,30 @@ class ClientAsyncReaderWriter final
   }
 
  private:
-  ClientAsyncReaderWriter(Call call, ClientContext* context, void* tag)
-      : context_(context), call_(call) {
-    if (context_->initial_metadata_corked_) {
-      // if corked bit is set in context, we buffer up the initial metadata to
-      // coalesce with later message to be sent. No op is performed.
-      write_ops_.SendInitialMetadata(context->send_initial_metadata_,
-                                     context->initial_metadata_flags());
+  ClientAsyncReaderWriter(Call call, ClientContext* context, bool start,
+                          void* tag)
+      : context_(context), call_(call), started_(start) {
+    if (start) {
+      StartCallInternal(tag);
     } else {
+      assert(tag == nullptr);
+    }
+  }
+
+  void StartCallInternal(void* tag) {
+    write_ops_.SendInitialMetadata(context_->send_initial_metadata_,
+                                   context_->initial_metadata_flags());
+    // if corked bit is set in context, we just keep the initial metadata
+    // buffered up to coalesce with later message send. No op is performed.
+    if (!context_->initial_metadata_corked_) {
       write_ops_.set_output_tag(tag);
-      write_ops_.SendInitialMetadata(context->send_initial_metadata_,
-                                     context->initial_metadata_flags());
       call_.PerformOps(&write_ops_);
     }
   }
 
   ClientContext* context_;
   Call call_;
+  bool started_;
   CallOpSet<CallOpRecvInitialMetadata> meta_ops_;
   CallOpSet<CallOpRecvInitialMetadata, CallOpRecvMessage<R>> read_ops_;
   CallOpSet<CallOpSendInitialMetadata, CallOpSendMessage, CallOpClientSendClose>
diff --git a/include/grpc++/impl/codegen/async_unary_call.h b/include/grpc++/impl/codegen/async_unary_call.h
index f0f909686bc..e472f04f56e 100644
--- a/include/grpc++/impl/codegen/async_unary_call.h
+++ b/include/grpc++/impl/codegen/async_unary_call.h
@@ -32,13 +32,18 @@ namespace grpc {
 class CompletionQueue;
 extern CoreCodegenInterface* g_core_codegen_interface;
 
-/// An interface relevant for async client side unary RPCS (which send
+/// An interface relevant for async client side unary RPCs (which send
 /// one request message to a server and receive one response message).
 template <class R>
 class ClientAsyncResponseReaderInterface {
  public:
   virtual ~ClientAsyncResponseReaderInterface() {}
 
+  /// Start the call that was set up by the constructor, but only if the
+  /// constructor was invoked through the "Prepare" API which doesn't actually
+  /// start the call
+  virtual void StartCall() = 0;
+
   /// Request notification of the reading of initial metadata. Completion
   /// will be notified by \a tag on the associated completion queue.
   /// This call is optional, but if it is used, it cannot be used concurrently
@@ -70,9 +75,10 @@ template <class R>
 class ClientAsyncResponseReader final
     : public ClientAsyncResponseReaderInterface<R> {
  public:
-  /// Start a call and write the request out.
+  /// Start a call and write the request out if \a start is set.
   /// \a tag will be notified on \a cq when the call has been started (i.e.
   /// intitial metadata sent) and \a request has been written out.
+  /// If \a start is not set, the actual call must be initiated by StartCall
   /// Note that \a context will be used to fill in custom initial metadata
   /// used to send to the server when starting the call.
   template <class W>
@@ -80,11 +86,11 @@ class ClientAsyncResponseReader final
                                            CompletionQueue* cq,
                                            const RpcMethod& method,
                                            ClientContext* context,
-                                           const W& request) {
+                                           const W& request, bool start) {
     Call call = channel->CreateCall(method, context, cq);
     return new (g_core_codegen_interface->grpc_call_arena_alloc(
         call.call(), sizeof(ClientAsyncResponseReader)))
-        ClientAsyncResponseReader(call, context, request);
+        ClientAsyncResponseReader(call, context, request, start);
   }
 
   // always allocated against a call arena, no memory free required
@@ -92,13 +98,20 @@ class ClientAsyncResponseReader final
     assert(size == sizeof(ClientAsyncResponseReader));
   }
 
+  void StartCall() override {
+    assert(!started_);
+    started_ = true;
+    StartCallInternal();
+  }
+
   /// See \a ClientAsyncResponseReaderInterface::ReadInitialMetadata for
   /// semantics.
   ///
   /// Side effect:
   ///   - the \a ClientContext associated with this call is updated with
   ///     possible initial and trailing metadata sent from the server.
-  void ReadInitialMetadata(void* tag) {
+  void ReadInitialMetadata(void* tag) override {
+    assert(started_);
     GPR_CODEGEN_ASSERT(!context_->initial_metadata_received_);
 
     meta_buf.set_output_tag(tag);
@@ -111,7 +124,8 @@ class ClientAsyncResponseReader final
   /// Side effect:
   ///   - the \a ClientContext associated with this call is updated with
   ///     possible initial and trailing metadata sent from the server.
-  void Finish(R* msg, Status* status, void* tag) {
+  void Finish(R* msg, Status* status, void* tag) override {
+    assert(started_);
     finish_buf.set_output_tag(tag);
     if (!context_->initial_metadata_received_) {
       finish_buf.RecvInitialMetadata(context_);
@@ -125,15 +139,22 @@ class ClientAsyncResponseReader final
  private:
   ClientContext* const context_;
   Call call_;
+  bool started_;
 
   template <class W>
-  ClientAsyncResponseReader(Call call, ClientContext* context, const W& request)
-      : context_(context), call_(call) {
-    init_buf.SendInitialMetadata(context->send_initial_metadata_,
-                                 context->initial_metadata_flags());
+  ClientAsyncResponseReader(Call call, ClientContext* context, const W& request,
+                            bool start)
+      : context_(context), call_(call), started_(start) {
+    // Bind the metadata at time of StartCallInternal but set up the rest here
     // TODO(ctiller): don't assert
     GPR_CODEGEN_ASSERT(init_buf.SendMessage(request).ok());
     init_buf.ClientSendClose();
+    if (start) StartCallInternal();
+  }
+
+  void StartCallInternal() {
+    init_buf.SendInitialMetadata(context_->send_initial_metadata_,
+                                 context_->initial_metadata_flags());
     call_.PerformOps(&init_buf);
   }
 
diff --git a/src/compiler/cpp_generator.cc b/src/compiler/cpp_generator.cc
index b09bf996774..c2db8eff714 100644
--- a/src/compiler/cpp_generator.cc
+++ b/src/compiler/cpp_generator.cc
@@ -165,25 +165,37 @@ void PrintHeaderClientMethodInterfaces(
   (*vars)["Request"] = method->input_type_name();
   (*vars)["Response"] = method->output_type_name();
 
+  struct {
+    grpc::string prefix;
+    grpc::string method_params;  // extra arguments to method
+    grpc::string raw_args;       // extra arguments to raw version of method
+  } async_prefixes[] = {{"Async", ", void* tag", ", tag"},
+                        {"PrepareAsync", "", ""}};
+
   if (is_public) {
     if (method->NoStreaming()) {
       printer->Print(
           *vars,
           "virtual ::grpc::Status $Method$(::grpc::ClientContext* context, "
           "const $Request$& request, $Response$* response) = 0;\n");
-      printer->Print(*vars,
-                     "std::unique_ptr< "
-                     "::grpc::ClientAsyncResponseReaderInterface< $Response$>> "
-                     "Async$Method$(::grpc::ClientContext* context, "
-                     "const $Request$& request, "
-                     "::grpc::CompletionQueue* cq) {\n");
-      printer->Indent();
-      printer->Print(*vars,
-                     "return std::unique_ptr< "
-                     "::grpc::ClientAsyncResponseReaderInterface< $Response$>>("
-                     "Async$Method$Raw(context, request, cq));\n");
-      printer->Outdent();
-      printer->Print("}\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        printer->Print(
+            *vars,
+            "std::unique_ptr< "
+            "::grpc::ClientAsyncResponseReaderInterface< $Response$>> "
+            "$AsyncPrefix$$Method$(::grpc::ClientContext* context, "
+            "const $Request$& request, "
+            "::grpc::CompletionQueue* cq) {\n");
+        printer->Indent();
+        printer->Print(
+            *vars,
+            "return std::unique_ptr< "
+            "::grpc::ClientAsyncResponseReaderInterface< $Response$>>("
+            "$AsyncPrefix$$Method$Raw(context, request, cq));\n");
+        printer->Outdent();
+        printer->Print("}\n");
+      }
     } else if (ClientOnlyStreaming(method)) {
       printer->Print(
           *vars,
@@ -197,19 +209,26 @@ void PrintHeaderClientMethodInterfaces(
           "($Method$Raw(context, response));\n");
       printer->Outdent();
       printer->Print("}\n");
-      printer->Print(
-          *vars,
-          "std::unique_ptr< ::grpc::ClientAsyncWriterInterface< $Request$>>"
-          " Async$Method$(::grpc::ClientContext* context, $Response$* "
-          "response, "
-          "::grpc::CompletionQueue* cq, void* tag) {\n");
-      printer->Indent();
-      printer->Print(*vars,
-                     "return std::unique_ptr< "
-                     "::grpc::ClientAsyncWriterInterface< $Request$>>("
-                     "Async$Method$Raw(context, response, cq, tag));\n");
-      printer->Outdent();
-      printer->Print("}\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+        (*vars)["AsyncRawArgs"] = async_prefix.raw_args;
+        printer->Print(
+            *vars,
+            "std::unique_ptr< ::grpc::ClientAsyncWriterInterface< $Request$>>"
+            " $AsyncPrefix$$Method$(::grpc::ClientContext* context, "
+            "$Response$* "
+            "response, "
+            "::grpc::CompletionQueue* cq$AsyncMethodParams$) {\n");
+        printer->Indent();
+        printer->Print(*vars,
+                       "return std::unique_ptr< "
+                       "::grpc::ClientAsyncWriterInterface< $Request$>>("
+                       "$AsyncPrefix$$Method$Raw(context, response, "
+                       "cq$AsyncRawArgs$));\n");
+        printer->Outdent();
+        printer->Print("}\n");
+      }
     } else if (ServerOnlyStreaming(method)) {
       printer->Print(
           *vars,
@@ -223,19 +242,25 @@ void PrintHeaderClientMethodInterfaces(
           "($Method$Raw(context, request));\n");
       printer->Outdent();
       printer->Print("}\n");
-      printer->Print(
-          *vars,
-          "std::unique_ptr< ::grpc::ClientAsyncReaderInterface< $Response$>> "
-          "Async$Method$("
-          "::grpc::ClientContext* context, const $Request$& request, "
-          "::grpc::CompletionQueue* cq, void* tag) {\n");
-      printer->Indent();
-      printer->Print(*vars,
-                     "return std::unique_ptr< "
-                     "::grpc::ClientAsyncReaderInterface< $Response$>>("
-                     "Async$Method$Raw(context, request, cq, tag));\n");
-      printer->Outdent();
-      printer->Print("}\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+        (*vars)["AsyncRawArgs"] = async_prefix.raw_args;
+        printer->Print(
+            *vars,
+            "std::unique_ptr< ::grpc::ClientAsyncReaderInterface< $Response$>> "
+            "$AsyncPrefix$$Method$("
+            "::grpc::ClientContext* context, const $Request$& request, "
+            "::grpc::CompletionQueue* cq$AsyncMethodParams$) {\n");
+        printer->Indent();
+        printer->Print(
+            *vars,
+            "return std::unique_ptr< "
+            "::grpc::ClientAsyncReaderInterface< $Response$>>("
+            "$AsyncPrefix$$Method$Raw(context, request, cq$AsyncRawArgs$));\n");
+        printer->Outdent();
+        printer->Print("}\n");
+      }
     } else if (method->BidiStreaming()) {
       printer->Print(*vars,
                      "std::unique_ptr< ::grpc::ClientReaderWriterInterface< "
@@ -249,61 +274,83 @@ void PrintHeaderClientMethodInterfaces(
           "$Method$Raw(context));\n");
       printer->Outdent();
       printer->Print("}\n");
-      printer->Print(
-          *vars,
-          "std::unique_ptr< "
-          "::grpc::ClientAsyncReaderWriterInterface< $Request$, $Response$>> "
-          "Async$Method$(::grpc::ClientContext* context, "
-          "::grpc::CompletionQueue* cq, void* tag) {\n");
-      printer->Indent();
-      printer->Print(
-          *vars,
-          "return std::unique_ptr< "
-          "::grpc::ClientAsyncReaderWriterInterface< $Request$, $Response$>>("
-          "Async$Method$Raw(context, cq, tag));\n");
-      printer->Outdent();
-      printer->Print("}\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+        (*vars)["AsyncRawArgs"] = async_prefix.raw_args;
+        printer->Print(
+            *vars,
+            "std::unique_ptr< "
+            "::grpc::ClientAsyncReaderWriterInterface< $Request$, $Response$>> "
+            "$AsyncPrefix$$Method$(::grpc::ClientContext* context, "
+            "::grpc::CompletionQueue* cq$AsyncMethodParams$) {\n");
+        printer->Indent();
+        printer->Print(
+            *vars,
+            "return std::unique_ptr< "
+            "::grpc::ClientAsyncReaderWriterInterface< $Request$, $Response$>>("
+            "$AsyncPrefix$$Method$Raw(context, cq$AsyncRawArgs$));\n");
+        printer->Outdent();
+        printer->Print("}\n");
+      }
     }
   } else {
     if (method->NoStreaming()) {
-      printer->Print(
-          *vars,
-          "virtual ::grpc::ClientAsyncResponseReaderInterface< $Response$>* "
-          "Async$Method$Raw(::grpc::ClientContext* context, "
-          "const $Request$& request, "
-          "::grpc::CompletionQueue* cq) = 0;\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        printer->Print(
+            *vars,
+            "virtual ::grpc::ClientAsyncResponseReaderInterface< $Response$>* "
+            "$AsyncPrefix$$Method$Raw(::grpc::ClientContext* context, "
+            "const $Request$& request, "
+            "::grpc::CompletionQueue* cq) = 0;\n");
+      }
     } else if (ClientOnlyStreaming(method)) {
       printer->Print(
           *vars,
           "virtual ::grpc::ClientWriterInterface< $Request$>*"
           " $Method$Raw("
           "::grpc::ClientContext* context, $Response$* response) = 0;\n");
-      printer->Print(*vars,
-                     "virtual ::grpc::ClientAsyncWriterInterface< $Request$>*"
-                     " Async$Method$Raw(::grpc::ClientContext* context, "
-                     "$Response$* response, "
-                     "::grpc::CompletionQueue* cq, void* tag) = 0;\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+        printer->Print(
+            *vars,
+            "virtual ::grpc::ClientAsyncWriterInterface< $Request$>*"
+            " $AsyncPrefix$$Method$Raw(::grpc::ClientContext* context, "
+            "$Response$* response, "
+            "::grpc::CompletionQueue* cq$AsyncMethodParams$) = 0;\n");
+      }
     } else if (ServerOnlyStreaming(method)) {
       printer->Print(
           *vars,
           "virtual ::grpc::ClientReaderInterface< $Response$>* $Method$Raw("
           "::grpc::ClientContext* context, const $Request$& request) = 0;\n");
-      printer->Print(
-          *vars,
-          "virtual ::grpc::ClientAsyncReaderInterface< $Response$>* "
-          "Async$Method$Raw("
-          "::grpc::ClientContext* context, const $Request$& request, "
-          "::grpc::CompletionQueue* cq, void* tag) = 0;\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+        printer->Print(
+            *vars,
+            "virtual ::grpc::ClientAsyncReaderInterface< $Response$>* "
+            "$AsyncPrefix$$Method$Raw("
+            "::grpc::ClientContext* context, const $Request$& request, "
+            "::grpc::CompletionQueue* cq$AsyncMethodParams$) = 0;\n");
+      }
     } else if (method->BidiStreaming()) {
       printer->Print(*vars,
                      "virtual ::grpc::ClientReaderWriterInterface< $Request$, "
                      "$Response$>* "
                      "$Method$Raw(::grpc::ClientContext* context) = 0;\n");
-      printer->Print(*vars,
-                     "virtual ::grpc::ClientAsyncReaderWriterInterface< "
-                     "$Request$, $Response$>* "
-                     "Async$Method$Raw(::grpc::ClientContext* context, "
-                     "::grpc::CompletionQueue* cq, void* tag) = 0;\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+        printer->Print(
+            *vars,
+            "virtual ::grpc::ClientAsyncReaderWriterInterface< "
+            "$Request$, $Response$>* "
+            "$AsyncPrefix$$Method$Raw(::grpc::ClientContext* context, "
+            "::grpc::CompletionQueue* cq$AsyncMethodParams$) = 0;\n");
+      }
     }
   }
 }
@@ -315,25 +362,35 @@ void PrintHeaderClientMethod(grpc_generator::Printer *printer,
   (*vars)["Method"] = method->name();
   (*vars)["Request"] = method->input_type_name();
   (*vars)["Response"] = method->output_type_name();
+  struct {
+    grpc::string prefix;
+    grpc::string method_params;  // extra arguments to method
+    grpc::string raw_args;       // extra arguments to raw version of method
+  } async_prefixes[] = {{"Async", ", void* tag", ", tag"},
+                        {"PrepareAsync", "", ""}};
+
   if (is_public) {
     if (method->NoStreaming()) {
       printer->Print(
           *vars,
           "::grpc::Status $Method$(::grpc::ClientContext* context, "
           "const $Request$& request, $Response$* response) override;\n");
-      printer->Print(
-          *vars,
-          "std::unique_ptr< ::grpc::ClientAsyncResponseReader< $Response$>> "
-          "Async$Method$(::grpc::ClientContext* context, "
-          "const $Request$& request, "
-          "::grpc::CompletionQueue* cq) {\n");
-      printer->Indent();
-      printer->Print(*vars,
-                     "return std::unique_ptr< "
-                     "::grpc::ClientAsyncResponseReader< $Response$>>("
-                     "Async$Method$Raw(context, request, cq));\n");
-      printer->Outdent();
-      printer->Print("}\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        printer->Print(
+            *vars,
+            "std::unique_ptr< ::grpc::ClientAsyncResponseReader< $Response$>> "
+            "$AsyncPrefix$$Method$(::grpc::ClientContext* context, "
+            "const $Request$& request, "
+            "::grpc::CompletionQueue* cq) {\n");
+        printer->Indent();
+        printer->Print(*vars,
+                       "return std::unique_ptr< "
+                       "::grpc::ClientAsyncResponseReader< $Response$>>("
+                       "$AsyncPrefix$$Method$Raw(context, request, cq));\n");
+        printer->Outdent();
+        printer->Print("}\n");
+      }
     } else if (ClientOnlyStreaming(method)) {
       printer->Print(
           *vars,
@@ -346,18 +403,24 @@ void PrintHeaderClientMethod(grpc_generator::Printer *printer,
                      "($Method$Raw(context, response));\n");
       printer->Outdent();
       printer->Print("}\n");
-      printer->Print(*vars,
-                     "std::unique_ptr< ::grpc::ClientAsyncWriter< $Request$>>"
-                     " Async$Method$(::grpc::ClientContext* context, "
-                     "$Response$* response, "
-                     "::grpc::CompletionQueue* cq, void* tag) {\n");
-      printer->Indent();
-      printer->Print(
-          *vars,
-          "return std::unique_ptr< ::grpc::ClientAsyncWriter< $Request$>>("
-          "Async$Method$Raw(context, response, cq, tag));\n");
-      printer->Outdent();
-      printer->Print("}\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+        (*vars)["AsyncRawArgs"] = async_prefix.raw_args;
+        printer->Print(*vars,
+                       "std::unique_ptr< ::grpc::ClientAsyncWriter< $Request$>>"
+                       " $AsyncPrefix$$Method$(::grpc::ClientContext* context, "
+                       "$Response$* response, "
+                       "::grpc::CompletionQueue* cq$AsyncMethodParams$) {\n");
+        printer->Indent();
+        printer->Print(
+            *vars,
+            "return std::unique_ptr< ::grpc::ClientAsyncWriter< $Request$>>("
+            "$AsyncPrefix$$Method$Raw(context, response, "
+            "cq$AsyncRawArgs$));\n");
+        printer->Outdent();
+        printer->Print("}\n");
+      }
     } else if (ServerOnlyStreaming(method)) {
       printer->Print(
           *vars,
@@ -371,19 +434,24 @@ void PrintHeaderClientMethod(grpc_generator::Printer *printer,
           "($Method$Raw(context, request));\n");
       printer->Outdent();
       printer->Print("}\n");
-      printer->Print(
-          *vars,
-          "std::unique_ptr< ::grpc::ClientAsyncReader< $Response$>> "
-          "Async$Method$("
-          "::grpc::ClientContext* context, const $Request$& request, "
-          "::grpc::CompletionQueue* cq, void* tag) {\n");
-      printer->Indent();
-      printer->Print(
-          *vars,
-          "return std::unique_ptr< ::grpc::ClientAsyncReader< $Response$>>("
-          "Async$Method$Raw(context, request, cq, tag));\n");
-      printer->Outdent();
-      printer->Print("}\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+        (*vars)["AsyncRawArgs"] = async_prefix.raw_args;
+        printer->Print(
+            *vars,
+            "std::unique_ptr< ::grpc::ClientAsyncReader< $Response$>> "
+            "$AsyncPrefix$$Method$("
+            "::grpc::ClientContext* context, const $Request$& request, "
+            "::grpc::CompletionQueue* cq$AsyncMethodParams$) {\n");
+        printer->Indent();
+        printer->Print(
+            *vars,
+            "return std::unique_ptr< ::grpc::ClientAsyncReader< $Response$>>("
+            "$AsyncPrefix$$Method$Raw(context, request, cq$AsyncRawArgs$));\n");
+        printer->Outdent();
+        printer->Print("}\n");
+      }
     } else if (method->BidiStreaming()) {
       printer->Print(
           *vars,
@@ -396,53 +464,80 @@ void PrintHeaderClientMethod(grpc_generator::Printer *printer,
                      "$Method$Raw(context));\n");
       printer->Outdent();
       printer->Print("}\n");
-      printer->Print(*vars,
-                     "std::unique_ptr<  ::grpc::ClientAsyncReaderWriter< "
-                     "$Request$, $Response$>> "
-                     "Async$Method$(::grpc::ClientContext* context, "
-                     "::grpc::CompletionQueue* cq, void* tag) {\n");
-      printer->Indent();
-      printer->Print(*vars,
-                     "return std::unique_ptr< "
-                     "::grpc::ClientAsyncReaderWriter< $Request$, $Response$>>("
-                     "Async$Method$Raw(context, cq, tag));\n");
-      printer->Outdent();
-      printer->Print("}\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+        (*vars)["AsyncRawArgs"] = async_prefix.raw_args;
+        printer->Print(*vars,
+                       "std::unique_ptr<  ::grpc::ClientAsyncReaderWriter< "
+                       "$Request$, $Response$>> "
+                       "$AsyncPrefix$$Method$(::grpc::ClientContext* context, "
+                       "::grpc::CompletionQueue* cq$AsyncMethodParams$) {\n");
+        printer->Indent();
+        printer->Print(
+            *vars,
+            "return std::unique_ptr< "
+            "::grpc::ClientAsyncReaderWriter< $Request$, $Response$>>("
+            "$AsyncPrefix$$Method$Raw(context, cq$AsyncRawArgs$));\n");
+        printer->Outdent();
+        printer->Print("}\n");
+      }
     }
   } else {
     if (method->NoStreaming()) {
-      printer->Print(*vars,
-                     "::grpc::ClientAsyncResponseReader< $Response$>* "
-                     "Async$Method$Raw(::grpc::ClientContext* context, "
-                     "const $Request$& request, "
-                     "::grpc::CompletionQueue* cq) override;\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        printer->Print(
+            *vars,
+            "::grpc::ClientAsyncResponseReader< $Response$>* "
+            "$AsyncPrefix$$Method$Raw(::grpc::ClientContext* context, "
+            "const $Request$& request, "
+            "::grpc::CompletionQueue* cq) override;\n");
+      }
     } else if (ClientOnlyStreaming(method)) {
       printer->Print(*vars,
                      "::grpc::ClientWriter< $Request$>* $Method$Raw("
                      "::grpc::ClientContext* context, $Response$* response) "
                      "override;\n");
-      printer->Print(*vars,
-                     "::grpc::ClientAsyncWriter< $Request$>* Async$Method$Raw("
-                     "::grpc::ClientContext* context, $Response$* response, "
-                     "::grpc::CompletionQueue* cq, void* tag) override;\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+        (*vars)["AsyncRawArgs"] = async_prefix.raw_args;
+        printer->Print(
+            *vars,
+            "::grpc::ClientAsyncWriter< $Request$>* $AsyncPrefix$$Method$Raw("
+            "::grpc::ClientContext* context, $Response$* response, "
+            "::grpc::CompletionQueue* cq$AsyncMethodParams$) override;\n");
+      }
     } else if (ServerOnlyStreaming(method)) {
       printer->Print(*vars,
                      "::grpc::ClientReader< $Response$>* $Method$Raw("
                      "::grpc::ClientContext* context, const $Request$& request)"
                      " override;\n");
-      printer->Print(
-          *vars,
-          "::grpc::ClientAsyncReader< $Response$>* Async$Method$Raw("
-          "::grpc::ClientContext* context, const $Request$& request, "
-          "::grpc::CompletionQueue* cq, void* tag) override;\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+        (*vars)["AsyncRawArgs"] = async_prefix.raw_args;
+        printer->Print(
+            *vars,
+            "::grpc::ClientAsyncReader< $Response$>* $AsyncPrefix$$Method$Raw("
+            "::grpc::ClientContext* context, const $Request$& request, "
+            "::grpc::CompletionQueue* cq$AsyncMethodParams$) override;\n");
+      }
     } else if (method->BidiStreaming()) {
       printer->Print(*vars,
                      "::grpc::ClientReaderWriter< $Request$, $Response$>* "
                      "$Method$Raw(::grpc::ClientContext* context) override;\n");
-      printer->Print(*vars,
-                     "::grpc::ClientAsyncReaderWriter< $Request$, $Response$>* "
-                     "Async$Method$Raw(::grpc::ClientContext* context, "
-                     "::grpc::CompletionQueue* cq, void* tag) override;\n");
+      for (auto async_prefix : async_prefixes) {
+        (*vars)["AsyncPrefix"] = async_prefix.prefix;
+        (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+        (*vars)["AsyncRawArgs"] = async_prefix.raw_args;
+        printer->Print(
+            *vars,
+            "::grpc::ClientAsyncReaderWriter< $Request$, $Response$>* "
+            "$AsyncPrefix$$Method$Raw(::grpc::ClientContext* context, "
+            "::grpc::CompletionQueue* cq$AsyncMethodParams$) override;\n");
+      }
     }
   }
 }
@@ -1077,6 +1172,13 @@ void PrintSourceClientMethod(grpc_generator::Printer *printer,
   (*vars)["Method"] = method->name();
   (*vars)["Request"] = method->input_type_name();
   (*vars)["Response"] = method->output_type_name();
+  struct {
+    grpc::string prefix;
+    grpc::string start;          // bool literal expressed as string
+    grpc::string method_params;  // extra arguments to method
+    grpc::string create_args;    // extra arguments to creator
+  } async_prefixes[] = {{"Async", "true", ", void* tag", ", tag"},
+                        {"PrepareAsync", "false", "", ", nullptr"}};
   if (method->NoStreaming()) {
     printer->Print(*vars,
                    "::grpc::Status $ns$$Service$::Stub::$Method$("
@@ -1087,19 +1189,23 @@ void PrintSourceClientMethod(grpc_generator::Printer *printer,
                    "rpcmethod_$Method$_, "
                    "context, request, response);\n"
                    "}\n\n");
-    printer->Print(
-        *vars,
-        "::grpc::ClientAsyncResponseReader< $Response$>* "
-        "$ns$$Service$::Stub::Async$Method$Raw(::grpc::ClientContext* context, "
-        "const $Request$& request, "
-        "::grpc::CompletionQueue* cq) {\n");
-    printer->Print(*vars,
-                   "  return "
-                   "::grpc::ClientAsyncResponseReader< $Response$>::Create("
-                   "channel_.get(), cq, "
-                   "rpcmethod_$Method$_, "
-                   "context, request);\n"
-                   "}\n\n");
+    for (auto async_prefix : async_prefixes) {
+      (*vars)["AsyncPrefix"] = async_prefix.prefix;
+      (*vars)["AsyncStart"] = async_prefix.start;
+      printer->Print(*vars,
+                     "::grpc::ClientAsyncResponseReader< $Response$>* "
+                     "$ns$$Service$::Stub::$AsyncPrefix$$Method$Raw(::grpc::"
+                     "ClientContext* context, "
+                     "const $Request$& request, "
+                     "::grpc::CompletionQueue* cq) {\n");
+      printer->Print(*vars,
+                     "  return "
+                     "::grpc::ClientAsyncResponseReader< $Response$>::Create("
+                     "channel_.get(), cq, "
+                     "rpcmethod_$Method$_, "
+                     "context, request, $AsyncStart$);\n"
+                     "}\n\n");
+    }
   } else if (ClientOnlyStreaming(method)) {
     printer->Print(*vars,
                    "::grpc::ClientWriter< $Request$>* "
@@ -1111,17 +1217,23 @@ void PrintSourceClientMethod(grpc_generator::Printer *printer,
                    "rpcmethod_$Method$_, "
                    "context, response);\n"
                    "}\n\n");
-    printer->Print(*vars,
-                   "::grpc::ClientAsyncWriter< $Request$>* "
-                   "$ns$$Service$::Stub::Async$Method$Raw("
-                   "::grpc::ClientContext* context, $Response$* response, "
-                   "::grpc::CompletionQueue* cq, void* tag) {\n");
-    printer->Print(*vars,
-                   "  return ::grpc::ClientAsyncWriter< $Request$>::Create("
-                   "channel_.get(), cq, "
-                   "rpcmethod_$Method$_, "
-                   "context, response, tag);\n"
-                   "}\n\n");
+    for (auto async_prefix : async_prefixes) {
+      (*vars)["AsyncPrefix"] = async_prefix.prefix;
+      (*vars)["AsyncStart"] = async_prefix.start;
+      (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+      (*vars)["AsyncCreateArgs"] = async_prefix.create_args;
+      printer->Print(*vars,
+                     "::grpc::ClientAsyncWriter< $Request$>* "
+                     "$ns$$Service$::Stub::$AsyncPrefix$$Method$Raw("
+                     "::grpc::ClientContext* context, $Response$* response, "
+                     "::grpc::CompletionQueue* cq$AsyncMethodParams$) {\n");
+      printer->Print(*vars,
+                     "  return ::grpc::ClientAsyncWriter< $Request$>::Create("
+                     "channel_.get(), cq, "
+                     "rpcmethod_$Method$_, "
+                     "context, response, $AsyncStart$$AsyncCreateArgs$);\n"
+                     "}\n\n");
+    }
   } else if (ServerOnlyStreaming(method)) {
     printer->Print(
         *vars,
@@ -1134,17 +1246,24 @@ void PrintSourceClientMethod(grpc_generator::Printer *printer,
                    "rpcmethod_$Method$_, "
                    "context, request);\n"
                    "}\n\n");
-    printer->Print(*vars,
-                   "::grpc::ClientAsyncReader< $Response$>* "
-                   "$ns$$Service$::Stub::Async$Method$Raw("
-                   "::grpc::ClientContext* context, const $Request$& request, "
-                   "::grpc::CompletionQueue* cq, void* tag) {\n");
-    printer->Print(*vars,
-                   "  return ::grpc::ClientAsyncReader< $Response$>::Create("
-                   "channel_.get(), cq, "
-                   "rpcmethod_$Method$_, "
-                   "context, request, tag);\n"
-                   "}\n\n");
+    for (auto async_prefix : async_prefixes) {
+      (*vars)["AsyncPrefix"] = async_prefix.prefix;
+      (*vars)["AsyncStart"] = async_prefix.start;
+      (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+      (*vars)["AsyncCreateArgs"] = async_prefix.create_args;
+      printer->Print(
+          *vars,
+          "::grpc::ClientAsyncReader< $Response$>* "
+          "$ns$$Service$::Stub::$AsyncPrefix$$Method$Raw("
+          "::grpc::ClientContext* context, const $Request$& request, "
+          "::grpc::CompletionQueue* cq$AsyncMethodParams$) {\n");
+      printer->Print(*vars,
+                     "  return ::grpc::ClientAsyncReader< $Response$>::Create("
+                     "channel_.get(), cq, "
+                     "rpcmethod_$Method$_, "
+                     "context, request, $AsyncStart$$AsyncCreateArgs$);\n"
+                     "}\n\n");
+    }
   } else if (method->BidiStreaming()) {
     printer->Print(
         *vars,
@@ -1157,19 +1276,25 @@ void PrintSourceClientMethod(grpc_generator::Printer *printer,
                    "rpcmethod_$Method$_, "
                    "context);\n"
                    "}\n\n");
-    printer->Print(
-        *vars,
-        "::grpc::ClientAsyncReaderWriter< $Request$, $Response$>* "
-        "$ns$$Service$::Stub::Async$Method$Raw(::grpc::ClientContext* context, "
-        "::grpc::CompletionQueue* cq, void* tag) {\n");
-    printer->Print(
-        *vars,
-        "  return "
-        "::grpc::ClientAsyncReaderWriter< $Request$, $Response$>::Create("
-        "channel_.get(), cq, "
-        "rpcmethod_$Method$_, "
-        "context, tag);\n"
-        "}\n\n");
+    for (auto async_prefix : async_prefixes) {
+      (*vars)["AsyncPrefix"] = async_prefix.prefix;
+      (*vars)["AsyncStart"] = async_prefix.start;
+      (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+      (*vars)["AsyncCreateArgs"] = async_prefix.create_args;
+      printer->Print(*vars,
+                     "::grpc::ClientAsyncReaderWriter< $Request$, $Response$>* "
+                     "$ns$$Service$::Stub::$AsyncPrefix$$Method$Raw(::grpc::"
+                     "ClientContext* context, "
+                     "::grpc::CompletionQueue* cq$AsyncMethodParams$) {\n");
+      printer->Print(
+          *vars,
+          "  return "
+          "::grpc::ClientAsyncReaderWriter< $Request$, $Response$>::Create("
+          "channel_.get(), cq, "
+          "rpcmethod_$Method$_, "
+          "context, $AsyncStart$$AsyncCreateArgs$);\n"
+          "}\n\n");
+    }
   }
 }
 
@@ -1460,50 +1585,79 @@ void PrintMockClientMethods(grpc_generator::Printer *printer,
   (*vars)["Request"] = method->input_type_name();
   (*vars)["Response"] = method->output_type_name();
 
+  struct {
+    grpc::string prefix;
+    grpc::string method_params;  // extra arguments to method
+    int extra_method_param_count;
+  } async_prefixes[] = {{"Async", ", void* tag", 1}, {"PrepareAsync", "", 0}};
+
   if (method->NoStreaming()) {
     printer->Print(
         *vars,
         "MOCK_METHOD3($Method$, ::grpc::Status(::grpc::ClientContext* context, "
         "const $Request$& request, $Response$* response));\n");
-    printer->Print(*vars,
-                   "MOCK_METHOD3(Async$Method$Raw, "
-                   "::grpc::ClientAsyncResponseReaderInterface< $Response$>*"
-                   "(::grpc::ClientContext* context, const $Request$& request, "
-                   "::grpc::CompletionQueue* cq));\n");
+    for (auto async_prefix : async_prefixes) {
+      (*vars)["AsyncPrefix"] = async_prefix.prefix;
+      printer->Print(
+          *vars,
+          "MOCK_METHOD3($AsyncPrefix$$Method$Raw, "
+          "::grpc::ClientAsyncResponseReaderInterface< $Response$>*"
+          "(::grpc::ClientContext* context, const $Request$& request, "
+          "::grpc::CompletionQueue* cq));\n");
+    }
   } else if (ClientOnlyStreaming(method)) {
     printer->Print(
         *vars,
         "MOCK_METHOD2($Method$Raw, "
         "::grpc::ClientWriterInterface< $Request$>*"
         "(::grpc::ClientContext* context, $Response$* response));\n");
-    printer->Print(*vars,
-                   "MOCK_METHOD4(Async$Method$Raw, "
-                   "::grpc::ClientAsyncWriterInterface< $Request$>*"
-                   "(::grpc::ClientContext* context, $Response$* response, "
-                   "::grpc::CompletionQueue* cq, void* tag));\n");
+    for (auto async_prefix : async_prefixes) {
+      (*vars)["AsyncPrefix"] = async_prefix.prefix;
+      (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+      (*vars)["MockArgs"] =
+          std::to_string(3 + async_prefix.extra_method_param_count);
+      printer->Print(*vars,
+                     "MOCK_METHOD$MockArgs$($AsyncPrefix$$Method$Raw, "
+                     "::grpc::ClientAsyncWriterInterface< $Request$>*"
+                     "(::grpc::ClientContext* context, $Response$* response, "
+                     "::grpc::CompletionQueue* cq$AsyncMethodParams$));\n");
+    }
   } else if (ServerOnlyStreaming(method)) {
     printer->Print(
         *vars,
         "MOCK_METHOD2($Method$Raw, "
         "::grpc::ClientReaderInterface< $Response$>*"
         "(::grpc::ClientContext* context, const $Request$& request));\n");
-    printer->Print(*vars,
-                   "MOCK_METHOD4(Async$Method$Raw, "
-                   "::grpc::ClientAsyncReaderInterface< $Response$>*"
-                   "(::grpc::ClientContext* context, const $Request$& request, "
-                   "::grpc::CompletionQueue* cq, void* tag));\n");
+    for (auto async_prefix : async_prefixes) {
+      (*vars)["AsyncPrefix"] = async_prefix.prefix;
+      (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+      (*vars)["MockArgs"] =
+          std::to_string(3 + async_prefix.extra_method_param_count);
+      printer->Print(
+          *vars,
+          "MOCK_METHOD$MockArgs$($AsyncPrefix$$Method$Raw, "
+          "::grpc::ClientAsyncReaderInterface< $Response$>*"
+          "(::grpc::ClientContext* context, const $Request$& request, "
+          "::grpc::CompletionQueue* cq$AsyncMethodParams$));\n");
+    }
   } else if (method->BidiStreaming()) {
     printer->Print(
         *vars,
         "MOCK_METHOD1($Method$Raw, "
         "::grpc::ClientReaderWriterInterface< $Request$, $Response$>*"
         "(::grpc::ClientContext* context));\n");
-    printer->Print(
-        *vars,
-        "MOCK_METHOD3(Async$Method$Raw, "
-        "::grpc::ClientAsyncReaderWriterInterface<$Request$, $Response$>*"
-        "(::grpc::ClientContext* context, ::grpc::CompletionQueue* cq, "
-        "void* tag));\n");
+    for (auto async_prefix : async_prefixes) {
+      (*vars)["AsyncPrefix"] = async_prefix.prefix;
+      (*vars)["AsyncMethodParams"] = async_prefix.method_params;
+      (*vars)["MockArgs"] =
+          std::to_string(2 + async_prefix.extra_method_param_count);
+      printer->Print(
+          *vars,
+          "MOCK_METHOD$MockArgs$($AsyncPrefix$$Method$Raw, "
+          "::grpc::ClientAsyncReaderWriterInterface<$Request$, $Response$>*"
+          "(::grpc::ClientContext* context, ::grpc::CompletionQueue* cq"
+          "$AsyncMethodParams$));\n");
+    }
   }
 }
 
diff --git a/src/cpp/client/generic_stub.cc b/src/cpp/client/generic_stub.cc
index 66b1ef0e39c..de2e449fe8f 100644
--- a/src/cpp/client/generic_stub.cc
+++ b/src/cpp/client/generic_stub.cc
@@ -22,14 +22,29 @@
 
 namespace grpc {
 
+namespace {
+std::unique_ptr<GenericClientAsyncReaderWriter> CallInternal(
+    ChannelInterface* channel, ClientContext* context,
+    const grpc::string& method, CompletionQueue* cq, bool start, void* tag) {
+  return std::unique_ptr<GenericClientAsyncReaderWriter>(
+      GenericClientAsyncReaderWriter::Create(
+          channel, cq, RpcMethod(method.c_str(), RpcMethod::BIDI_STREAMING),
+          context, start, tag));
+}
+
+}  // namespace
+
 // begin a call to a named method
 std::unique_ptr<GenericClientAsyncReaderWriter> GenericStub::Call(
     ClientContext* context, const grpc::string& method, CompletionQueue* cq,
     void* tag) {
-  return std::unique_ptr<GenericClientAsyncReaderWriter>(
-      GenericClientAsyncReaderWriter::Create(
-          channel_.get(), cq,
-          RpcMethod(method.c_str(), RpcMethod::BIDI_STREAMING), context, tag));
+  return CallInternal(channel_.get(), context, method, cq, true, tag);
+}
+
+// setup a call to a named method
+std::unique_ptr<GenericClientAsyncReaderWriter> GenericStub::PrepareCall(
+    ClientContext* context, const grpc::string& method, CompletionQueue* cq) {
+  return CallInternal(channel_.get(), context, method, cq, false, nullptr);
 }
 
 }  // namespace grpc
diff --git a/test/cpp/codegen/compiler_test_golden b/test/cpp/codegen/compiler_test_golden
index b43c27f3f77..3d664e88254 100644
--- a/test/cpp/codegen/compiler_test_golden
+++ b/test/cpp/codegen/compiler_test_golden
@@ -65,6 +65,9 @@ class ServiceA final {
     std::unique_ptr< ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>> AsyncMethodA1(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) {
       return std::unique_ptr< ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>>(AsyncMethodA1Raw(context, request, cq));
     }
+    std::unique_ptr< ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>> PrepareAsyncMethodA1(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) {
+      return std::unique_ptr< ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>>(PrepareAsyncMethodA1Raw(context, request, cq));
+    }
     // MethodA1 trailing comment 1
     // MethodA2 detached leading comment 1
     //
@@ -76,6 +79,9 @@ class ServiceA final {
     std::unique_ptr< ::grpc::ClientAsyncWriterInterface< ::grpc::testing::Request>> AsyncMethodA2(::grpc::ClientContext* context, ::grpc::testing::Response* response, ::grpc::CompletionQueue* cq, void* tag) {
       return std::unique_ptr< ::grpc::ClientAsyncWriterInterface< ::grpc::testing::Request>>(AsyncMethodA2Raw(context, response, cq, tag));
     }
+    std::unique_ptr< ::grpc::ClientAsyncWriterInterface< ::grpc::testing::Request>> PrepareAsyncMethodA2(::grpc::ClientContext* context, ::grpc::testing::Response* response, ::grpc::CompletionQueue* cq) {
+      return std::unique_ptr< ::grpc::ClientAsyncWriterInterface< ::grpc::testing::Request>>(PrepareAsyncMethodA2Raw(context, response, cq));
+    }
     // MethodA2 trailing comment 1
     // Method A3 leading comment 1
     std::unique_ptr< ::grpc::ClientReaderInterface< ::grpc::testing::Response>> MethodA3(::grpc::ClientContext* context, const ::grpc::testing::Request& request) {
@@ -84,6 +90,9 @@ class ServiceA final {
     std::unique_ptr< ::grpc::ClientAsyncReaderInterface< ::grpc::testing::Response>> AsyncMethodA3(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq, void* tag) {
       return std::unique_ptr< ::grpc::ClientAsyncReaderInterface< ::grpc::testing::Response>>(AsyncMethodA3Raw(context, request, cq, tag));
     }
+    std::unique_ptr< ::grpc::ClientAsyncReaderInterface< ::grpc::testing::Response>> PrepareAsyncMethodA3(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) {
+      return std::unique_ptr< ::grpc::ClientAsyncReaderInterface< ::grpc::testing::Response>>(PrepareAsyncMethodA3Raw(context, request, cq));
+    }
     // Method A3 trailing comment 1
     // Method A4 leading comment 1
     std::unique_ptr< ::grpc::ClientReaderWriterInterface< ::grpc::testing::Request, ::grpc::testing::Response>> MethodA4(::grpc::ClientContext* context) {
@@ -92,15 +101,22 @@ class ServiceA final {
     std::unique_ptr< ::grpc::ClientAsyncReaderWriterInterface< ::grpc::testing::Request, ::grpc::testing::Response>> AsyncMethodA4(::grpc::ClientContext* context, ::grpc::CompletionQueue* cq, void* tag) {
       return std::unique_ptr< ::grpc::ClientAsyncReaderWriterInterface< ::grpc::testing::Request, ::grpc::testing::Response>>(AsyncMethodA4Raw(context, cq, tag));
     }
+    std::unique_ptr< ::grpc::ClientAsyncReaderWriterInterface< ::grpc::testing::Request, ::grpc::testing::Response>> PrepareAsyncMethodA4(::grpc::ClientContext* context, ::grpc::CompletionQueue* cq) {
+      return std::unique_ptr< ::grpc::ClientAsyncReaderWriterInterface< ::grpc::testing::Request, ::grpc::testing::Response>>(PrepareAsyncMethodA4Raw(context, cq));
+    }
     // Method A4 trailing comment 1
   private:
     virtual ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>* AsyncMethodA1Raw(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) = 0;
+    virtual ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>* PrepareAsyncMethodA1Raw(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) = 0;
     virtual ::grpc::ClientWriterInterface< ::grpc::testing::Request>* MethodA2Raw(::grpc::ClientContext* context, ::grpc::testing::Response* response) = 0;
     virtual ::grpc::ClientAsyncWriterInterface< ::grpc::testing::Request>* AsyncMethodA2Raw(::grpc::ClientContext* context, ::grpc::testing::Response* response, ::grpc::CompletionQueue* cq, void* tag) = 0;
+    virtual ::grpc::ClientAsyncWriterInterface< ::grpc::testing::Request>* PrepareAsyncMethodA2Raw(::grpc::ClientContext* context, ::grpc::testing::Response* response, ::grpc::CompletionQueue* cq) = 0;
     virtual ::grpc::ClientReaderInterface< ::grpc::testing::Response>* MethodA3Raw(::grpc::ClientContext* context, const ::grpc::testing::Request& request) = 0;
     virtual ::grpc::ClientAsyncReaderInterface< ::grpc::testing::Response>* AsyncMethodA3Raw(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq, void* tag) = 0;
+    virtual ::grpc::ClientAsyncReaderInterface< ::grpc::testing::Response>* PrepareAsyncMethodA3Raw(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) = 0;
     virtual ::grpc::ClientReaderWriterInterface< ::grpc::testing::Request, ::grpc::testing::Response>* MethodA4Raw(::grpc::ClientContext* context) = 0;
     virtual ::grpc::ClientAsyncReaderWriterInterface< ::grpc::testing::Request, ::grpc::testing::Response>* AsyncMethodA4Raw(::grpc::ClientContext* context, ::grpc::CompletionQueue* cq, void* tag) = 0;
+    virtual ::grpc::ClientAsyncReaderWriterInterface< ::grpc::testing::Request, ::grpc::testing::Response>* PrepareAsyncMethodA4Raw(::grpc::ClientContext* context, ::grpc::CompletionQueue* cq) = 0;
   };
   class Stub final : public StubInterface {
    public:
@@ -109,34 +125,50 @@ class ServiceA final {
     std::unique_ptr< ::grpc::ClientAsyncResponseReader< ::grpc::testing::Response>> AsyncMethodA1(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) {
       return std::unique_ptr< ::grpc::ClientAsyncResponseReader< ::grpc::testing::Response>>(AsyncMethodA1Raw(context, request, cq));
     }
+    std::unique_ptr< ::grpc::ClientAsyncResponseReader< ::grpc::testing::Response>> PrepareAsyncMethodA1(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) {
+      return std::unique_ptr< ::grpc::ClientAsyncResponseReader< ::grpc::testing::Response>>(PrepareAsyncMethodA1Raw(context, request, cq));
+    }
     std::unique_ptr< ::grpc::ClientWriter< ::grpc::testing::Request>> MethodA2(::grpc::ClientContext* context, ::grpc::testing::Response* response) {
       return std::unique_ptr< ::grpc::ClientWriter< ::grpc::testing::Request>>(MethodA2Raw(context, response));
     }
     std::unique_ptr< ::grpc::ClientAsyncWriter< ::grpc::testing::Request>> AsyncMethodA2(::grpc::ClientContext* context, ::grpc::testing::Response* response, ::grpc::CompletionQueue* cq, void* tag) {
       return std::unique_ptr< ::grpc::ClientAsyncWriter< ::grpc::testing::Request>>(AsyncMethodA2Raw(context, response, cq, tag));
     }
+    std::unique_ptr< ::grpc::ClientAsyncWriter< ::grpc::testing::Request>> PrepareAsyncMethodA2(::grpc::ClientContext* context, ::grpc::testing::Response* response, ::grpc::CompletionQueue* cq) {
+      return std::unique_ptr< ::grpc::ClientAsyncWriter< ::grpc::testing::Request>>(PrepareAsyncMethodA2Raw(context, response, cq));
+    }
     std::unique_ptr< ::grpc::ClientReader< ::grpc::testing::Response>> MethodA3(::grpc::ClientContext* context, const ::grpc::testing::Request& request) {
       return std::unique_ptr< ::grpc::ClientReader< ::grpc::testing::Response>>(MethodA3Raw(context, request));
     }
     std::unique_ptr< ::grpc::ClientAsyncReader< ::grpc::testing::Response>> AsyncMethodA3(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq, void* tag) {
       return std::unique_ptr< ::grpc::ClientAsyncReader< ::grpc::testing::Response>>(AsyncMethodA3Raw(context, request, cq, tag));
     }
+    std::unique_ptr< ::grpc::ClientAsyncReader< ::grpc::testing::Response>> PrepareAsyncMethodA3(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) {
+      return std::unique_ptr< ::grpc::ClientAsyncReader< ::grpc::testing::Response>>(PrepareAsyncMethodA3Raw(context, request, cq));
+    }
     std::unique_ptr< ::grpc::ClientReaderWriter< ::grpc::testing::Request, ::grpc::testing::Response>> MethodA4(::grpc::ClientContext* context) {
       return std::unique_ptr< ::grpc::ClientReaderWriter< ::grpc::testing::Request, ::grpc::testing::Response>>(MethodA4Raw(context));
     }
     std::unique_ptr<  ::grpc::ClientAsyncReaderWriter< ::grpc::testing::Request, ::grpc::testing::Response>> AsyncMethodA4(::grpc::ClientContext* context, ::grpc::CompletionQueue* cq, void* tag) {
       return std::unique_ptr< ::grpc::ClientAsyncReaderWriter< ::grpc::testing::Request, ::grpc::testing::Response>>(AsyncMethodA4Raw(context, cq, tag));
     }
+    std::unique_ptr<  ::grpc::ClientAsyncReaderWriter< ::grpc::testing::Request, ::grpc::testing::Response>> PrepareAsyncMethodA4(::grpc::ClientContext* context, ::grpc::CompletionQueue* cq) {
+      return std::unique_ptr< ::grpc::ClientAsyncReaderWriter< ::grpc::testing::Request, ::grpc::testing::Response>>(PrepareAsyncMethodA4Raw(context, cq));
+    }
 
    private:
     std::shared_ptr< ::grpc::ChannelInterface> channel_;
     ::grpc::ClientAsyncResponseReader< ::grpc::testing::Response>* AsyncMethodA1Raw(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) override;
+    ::grpc::ClientAsyncResponseReader< ::grpc::testing::Response>* PrepareAsyncMethodA1Raw(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) override;
     ::grpc::ClientWriter< ::grpc::testing::Request>* MethodA2Raw(::grpc::ClientContext* context, ::grpc::testing::Response* response) override;
     ::grpc::ClientAsyncWriter< ::grpc::testing::Request>* AsyncMethodA2Raw(::grpc::ClientContext* context, ::grpc::testing::Response* response, ::grpc::CompletionQueue* cq, void* tag) override;
+    ::grpc::ClientAsyncWriter< ::grpc::testing::Request>* PrepareAsyncMethodA2Raw(::grpc::ClientContext* context, ::grpc::testing::Response* response, ::grpc::CompletionQueue* cq) override;
     ::grpc::ClientReader< ::grpc::testing::Response>* MethodA3Raw(::grpc::ClientContext* context, const ::grpc::testing::Request& request) override;
     ::grpc::ClientAsyncReader< ::grpc::testing::Response>* AsyncMethodA3Raw(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq, void* tag) override;
+    ::grpc::ClientAsyncReader< ::grpc::testing::Response>* PrepareAsyncMethodA3Raw(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) override;
     ::grpc::ClientReaderWriter< ::grpc::testing::Request, ::grpc::testing::Response>* MethodA4Raw(::grpc::ClientContext* context) override;
     ::grpc::ClientAsyncReaderWriter< ::grpc::testing::Request, ::grpc::testing::Response>* AsyncMethodA4Raw(::grpc::ClientContext* context, ::grpc::CompletionQueue* cq, void* tag) override;
+    ::grpc::ClientAsyncReaderWriter< ::grpc::testing::Request, ::grpc::testing::Response>* PrepareAsyncMethodA4Raw(::grpc::ClientContext* context, ::grpc::CompletionQueue* cq) override;
     const ::grpc::RpcMethod rpcmethod_MethodA1_;
     const ::grpc::RpcMethod rpcmethod_MethodA2_;
     const ::grpc::RpcMethod rpcmethod_MethodA3_;
@@ -372,9 +404,13 @@ class ServiceB final {
     std::unique_ptr< ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>> AsyncMethodB1(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) {
       return std::unique_ptr< ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>>(AsyncMethodB1Raw(context, request, cq));
     }
+    std::unique_ptr< ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>> PrepareAsyncMethodB1(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) {
+      return std::unique_ptr< ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>>(PrepareAsyncMethodB1Raw(context, request, cq));
+    }
     // MethodB1 trailing comment 1
   private:
     virtual ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>* AsyncMethodB1Raw(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) = 0;
+    virtual ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>* PrepareAsyncMethodB1Raw(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) = 0;
   };
   class Stub final : public StubInterface {
    public:
@@ -383,10 +419,14 @@ class ServiceB final {
     std::unique_ptr< ::grpc::ClientAsyncResponseReader< ::grpc::testing::Response>> AsyncMethodB1(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) {
       return std::unique_ptr< ::grpc::ClientAsyncResponseReader< ::grpc::testing::Response>>(AsyncMethodB1Raw(context, request, cq));
     }
+    std::unique_ptr< ::grpc::ClientAsyncResponseReader< ::grpc::testing::Response>> PrepareAsyncMethodB1(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) {
+      return std::unique_ptr< ::grpc::ClientAsyncResponseReader< ::grpc::testing::Response>>(PrepareAsyncMethodB1Raw(context, request, cq));
+    }
 
    private:
     std::shared_ptr< ::grpc::ChannelInterface> channel_;
     ::grpc::ClientAsyncResponseReader< ::grpc::testing::Response>* AsyncMethodB1Raw(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) override;
+    ::grpc::ClientAsyncResponseReader< ::grpc::testing::Response>* PrepareAsyncMethodB1Raw(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq) override;
     const ::grpc::RpcMethod rpcmethod_MethodB1_;
   };
   static std::unique_ptr<Stub> NewStub(const std::shared_ptr< ::grpc::ChannelInterface>& channel, const ::grpc::StubOptions& options = ::grpc::StubOptions());
diff --git a/test/cpp/codegen/compiler_test_mock_golden b/test/cpp/codegen/compiler_test_mock_golden
index 8e4b4d59112..f97c2dd83a4 100644
--- a/test/cpp/codegen/compiler_test_mock_golden
+++ b/test/cpp/codegen/compiler_test_mock_golden
@@ -15,18 +15,23 @@ class MockServiceAStub : public ServiceA::StubInterface {
  public:
   MOCK_METHOD3(MethodA1, ::grpc::Status(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::testing::Response* response));
   MOCK_METHOD3(AsyncMethodA1Raw, ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>*(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq));
+  MOCK_METHOD3(PrepareAsyncMethodA1Raw, ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>*(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq));
   MOCK_METHOD2(MethodA2Raw, ::grpc::ClientWriterInterface< ::grpc::testing::Request>*(::grpc::ClientContext* context, ::grpc::testing::Response* response));
   MOCK_METHOD4(AsyncMethodA2Raw, ::grpc::ClientAsyncWriterInterface< ::grpc::testing::Request>*(::grpc::ClientContext* context, ::grpc::testing::Response* response, ::grpc::CompletionQueue* cq, void* tag));
+  MOCK_METHOD3(PrepareAsyncMethodA2Raw, ::grpc::ClientAsyncWriterInterface< ::grpc::testing::Request>*(::grpc::ClientContext* context, ::grpc::testing::Response* response, ::grpc::CompletionQueue* cq));
   MOCK_METHOD2(MethodA3Raw, ::grpc::ClientReaderInterface< ::grpc::testing::Response>*(::grpc::ClientContext* context, const ::grpc::testing::Request& request));
   MOCK_METHOD4(AsyncMethodA3Raw, ::grpc::ClientAsyncReaderInterface< ::grpc::testing::Response>*(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq, void* tag));
+  MOCK_METHOD3(PrepareAsyncMethodA3Raw, ::grpc::ClientAsyncReaderInterface< ::grpc::testing::Response>*(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq));
   MOCK_METHOD1(MethodA4Raw, ::grpc::ClientReaderWriterInterface< ::grpc::testing::Request, ::grpc::testing::Response>*(::grpc::ClientContext* context));
   MOCK_METHOD3(AsyncMethodA4Raw, ::grpc::ClientAsyncReaderWriterInterface<::grpc::testing::Request, ::grpc::testing::Response>*(::grpc::ClientContext* context, ::grpc::CompletionQueue* cq, void* tag));
+  MOCK_METHOD2(PrepareAsyncMethodA4Raw, ::grpc::ClientAsyncReaderWriterInterface<::grpc::testing::Request, ::grpc::testing::Response>*(::grpc::ClientContext* context, ::grpc::CompletionQueue* cq));
 };
 
 class MockServiceBStub : public ServiceB::StubInterface {
  public:
   MOCK_METHOD3(MethodB1, ::grpc::Status(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::testing::Response* response));
   MOCK_METHOD3(AsyncMethodB1Raw, ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>*(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq));
+  MOCK_METHOD3(PrepareAsyncMethodB1Raw, ::grpc::ClientAsyncResponseReaderInterface< ::grpc::testing::Response>*(::grpc::ClientContext* context, const ::grpc::testing::Request& request, ::grpc::CompletionQueue* cq));
 };
 
 } // namespace grpc
diff --git a/test/cpp/qps/client_async.cc b/test/cpp/qps/client_async.cc
index 912c871482a..1a4438047dd 100644
--- a/test/cpp/qps/client_async.cc
+++ b/test/cpp/qps/client_async.cc
@@ -56,11 +56,6 @@ class ClientRpcContext {
   }
 
   virtual void Start(CompletionQueue* cq, const ClientConfig& config) = 0;
-  void lock() { mu_.lock(); }
-  void unlock() { mu_.unlock(); }
-
- private:
-  std::mutex mu_;
 };
 
 template <class RequestType, class ResponseType>
@@ -73,7 +68,7 @@ class ClientRpcContextUnaryImpl : public ClientRpcContext {
           std::unique_ptr<grpc::ClientAsyncResponseReader<ResponseType>>(
               BenchmarkService::Stub*, grpc::ClientContext*, const RequestType&,
               CompletionQueue*)>
-          start_req,
+          prepare_req,
       std::function<void(grpc::Status, ResponseType*, HistogramEntry*)> on_done)
       : context_(),
         stub_(stub),
@@ -83,7 +78,7 @@ class ClientRpcContextUnaryImpl : public ClientRpcContext {
         next_state_(State::READY),
         callback_(on_done),
         next_issue_(next_issue),
-        start_req_(start_req) {}
+        prepare_req_(prepare_req) {}
   ~ClientRpcContextUnaryImpl() override {}
   void Start(CompletionQueue* cq, const ClientConfig& config) override {
     StartInternal(cq);
@@ -92,7 +87,8 @@ class ClientRpcContextUnaryImpl : public ClientRpcContext {
     switch (next_state_) {
       case State::READY:
         start_ = UsageTimer::Now();
-        response_reader_ = start_req_(stub_, &context_, req_, cq_);
+        response_reader_ = prepare_req_(stub_, &context_, req_, cq_);
+        response_reader_->StartCall();
         next_state_ = State::RESP_DONE;
         response_reader_->Finish(&response_, &status_,
                                  ClientRpcContext::tag(this));
@@ -111,8 +107,7 @@ class ClientRpcContextUnaryImpl : public ClientRpcContext {
   }
   void StartNewClone(CompletionQueue* cq) override {
     auto* clone = new ClientRpcContextUnaryImpl(stub_, req_, next_issue_,
-                                                start_req_, callback_);
-    std::lock_guard<ClientRpcContext> lclone(*clone);
+                                                prepare_req_, callback_);
     clone->StartInternal(cq);
   }
 
@@ -130,7 +125,7 @@ class ClientRpcContextUnaryImpl : public ClientRpcContext {
   std::function<std::unique_ptr<grpc::ClientAsyncResponseReader<ResponseType>>(
       BenchmarkService::Stub*, grpc::ClientContext*, const RequestType&,
       CompletionQueue*)>
-      start_req_;
+      prepare_req_;
   grpc::Status status_;
   double start_;
   std::unique_ptr<grpc::ClientAsyncResponseReader<ResponseType>>
@@ -252,29 +247,13 @@ class AsyncClient : public ClientImpl<StubType, RequestType> {
       // this thread isn't supposed to shut down
       std::lock_guard<std::mutex> l(shutdown_state_[thread_idx]->mutex);
       if (shutdown_state_[thread_idx]->shutdown) {
-        // We want to delete the context. However, it is possible that
-        // another thread that just initiated an action on this
-        // context still has its lock even though the action on the
-        // context has completed. To delay for that, just grab the
-        // lock for serialization. Take a new scope.
-        { std::lock_guard<ClientRpcContext> lctx(*ctx); }
         delete ctx;
         return true;
       }
-      bool del = false;
-
-      // Create a new scope for a lock_guard'ed region
-      {
-        std::lock_guard<ClientRpcContext> lctx(*ctx);
-        if (!ctx->RunNextState(ok, entry)) {
-          // The RPC and callback are done, so clone the ctx
-          // and kickstart the new one
-          ctx->StartNewClone(cli_cqs_[cq_[thread_idx]].get());
-          // set the old version to delete
-          del = true;
-        }
-      }
-      if (del) {
+      if (!ctx->RunNextState(ok, entry)) {
+        // The RPC and callback are done, so clone the ctx
+        // and kickstart the new one
+        ctx->StartNewClone(cli_cqs_[cq_[thread_idx]].get());
         delete ctx;
       }
       return true;
@@ -311,15 +290,15 @@ class AsyncUnaryClient final
     entry->set_status(s.error_code());
   }
   static std::unique_ptr<grpc::ClientAsyncResponseReader<SimpleResponse>>
-  StartReq(BenchmarkService::Stub* stub, grpc::ClientContext* ctx,
-           const SimpleRequest& request, CompletionQueue* cq) {
-    return stub->AsyncUnaryCall(ctx, request, cq);
+  PrepareReq(BenchmarkService::Stub* stub, grpc::ClientContext* ctx,
+             const SimpleRequest& request, CompletionQueue* cq) {
+    return stub->PrepareAsyncUnaryCall(ctx, request, cq);
   };
   static ClientRpcContext* SetupCtx(BenchmarkService::Stub* stub,
                                     std::function<gpr_timespec()> next_issue,
                                     const SimpleRequest& req) {
     return new ClientRpcContextUnaryImpl<SimpleRequest, SimpleResponse>(
-        stub, req, next_issue, AsyncUnaryClient::StartReq,
+        stub, req, next_issue, AsyncUnaryClient::PrepareReq,
         AsyncUnaryClient::CheckDone);
   }
 };
@@ -332,9 +311,8 @@ class ClientRpcContextStreamingPingPongImpl : public ClientRpcContext {
       std::function<gpr_timespec()> next_issue,
       std::function<std::unique_ptr<
           grpc::ClientAsyncReaderWriter<RequestType, ResponseType>>(
-          BenchmarkService::Stub*, grpc::ClientContext*, CompletionQueue*,
-          void*)>
-          start_req,
+          BenchmarkService::Stub*, grpc::ClientContext*, CompletionQueue*)>
+          prepare_req,
       std::function<void(grpc::Status, ResponseType*)> on_done)
       : context_(),
         stub_(stub),
@@ -344,7 +322,7 @@ class ClientRpcContextStreamingPingPongImpl : public ClientRpcContext {
         next_state_(State::INVALID),
         callback_(on_done),
         next_issue_(next_issue),
-        start_req_(start_req) {}
+        prepare_req_(prepare_req) {}
   ~ClientRpcContextStreamingPingPongImpl() override {}
   void Start(CompletionQueue* cq, const ClientConfig& config) override {
     StartInternal(cq, config.messages_per_stream());
@@ -407,8 +385,7 @@ class ClientRpcContextStreamingPingPongImpl : public ClientRpcContext {
   }
   void StartNewClone(CompletionQueue* cq) override {
     auto* clone = new ClientRpcContextStreamingPingPongImpl(
-        stub_, req_, next_issue_, start_req_, callback_);
-    std::lock_guard<ClientRpcContext> lclone(*clone);
+        stub_, req_, next_issue_, prepare_req_, callback_);
     clone->StartInternal(cq, messages_per_stream_);
   }
 
@@ -432,10 +409,10 @@ class ClientRpcContextStreamingPingPongImpl : public ClientRpcContext {
   State next_state_;
   std::function<void(grpc::Status, ResponseType*)> callback_;
   std::function<gpr_timespec()> next_issue_;
-  std::function<std::unique_ptr<
-      grpc::ClientAsyncReaderWriter<RequestType, ResponseType>>(
-      BenchmarkService::Stub*, grpc::ClientContext*, CompletionQueue*, void*)>
-      start_req_;
+  std::function<
+      std::unique_ptr<grpc::ClientAsyncReaderWriter<RequestType, ResponseType>>(
+          BenchmarkService::Stub*, grpc::ClientContext*, CompletionQueue*)>
+      prepare_req_;
   grpc::Status status_;
   double start_;
   std::unique_ptr<grpc::ClientAsyncReaderWriter<RequestType, ResponseType>>
@@ -449,8 +426,9 @@ class ClientRpcContextStreamingPingPongImpl : public ClientRpcContext {
     cq_ = cq;
     messages_per_stream_ = messages_per_stream;
     messages_issued_ = 0;
+    stream_ = prepare_req_(stub_, &context_, cq);
     next_state_ = State::STREAM_IDLE;
-    stream_ = start_req_(stub_, &context_, cq, ClientRpcContext::tag(this));
+    stream_->StartCall(ClientRpcContext::tag(this));
   }
 };
 
@@ -469,9 +447,9 @@ class AsyncStreamingPingPongClient final
   static void CheckDone(grpc::Status s, SimpleResponse* response) {}
   static std::unique_ptr<
       grpc::ClientAsyncReaderWriter<SimpleRequest, SimpleResponse>>
-  StartReq(BenchmarkService::Stub* stub, grpc::ClientContext* ctx,
-           CompletionQueue* cq, void* tag) {
-    auto stream = stub->AsyncStreamingCall(ctx, cq, tag);
+  PrepareReq(BenchmarkService::Stub* stub, grpc::ClientContext* ctx,
+             CompletionQueue* cq) {
+    auto stream = stub->PrepareAsyncStreamingCall(ctx, cq);
     return stream;
   };
   static ClientRpcContext* SetupCtx(BenchmarkService::Stub* stub,
@@ -479,7 +457,7 @@ class AsyncStreamingPingPongClient final
                                     const SimpleRequest& req) {
     return new ClientRpcContextStreamingPingPongImpl<SimpleRequest,
                                                      SimpleResponse>(
-        stub, req, next_issue, AsyncStreamingPingPongClient::StartReq,
+        stub, req, next_issue, AsyncStreamingPingPongClient::PrepareReq,
         AsyncStreamingPingPongClient::CheckDone);
   }
 };
@@ -492,8 +470,8 @@ class ClientRpcContextStreamingFromClientImpl : public ClientRpcContext {
       std::function<gpr_timespec()> next_issue,
       std::function<std::unique_ptr<grpc::ClientAsyncWriter<RequestType>>(
           BenchmarkService::Stub*, grpc::ClientContext*, ResponseType*,
-          CompletionQueue*, void*)>
-          start_req,
+          CompletionQueue*)>
+          prepare_req,
       std::function<void(grpc::Status, ResponseType*)> on_done)
       : context_(),
         stub_(stub),
@@ -503,7 +481,7 @@ class ClientRpcContextStreamingFromClientImpl : public ClientRpcContext {
         next_state_(State::INVALID),
         callback_(on_done),
         next_issue_(next_issue),
-        start_req_(start_req) {}
+        prepare_req_(prepare_req) {}
   ~ClientRpcContextStreamingFromClientImpl() override {}
   void Start(CompletionQueue* cq, const ClientConfig& config) override {
     StartInternal(cq);
@@ -546,8 +524,7 @@ class ClientRpcContextStreamingFromClientImpl : public ClientRpcContext {
   }
   void StartNewClone(CompletionQueue* cq) override {
     auto* clone = new ClientRpcContextStreamingFromClientImpl(
-        stub_, req_, next_issue_, start_req_, callback_);
-    std::lock_guard<ClientRpcContext> lclone(*clone);
+        stub_, req_, next_issue_, prepare_req_, callback_);
     clone->StartInternal(cq);
   }
 
@@ -570,17 +547,17 @@ class ClientRpcContextStreamingFromClientImpl : public ClientRpcContext {
   std::function<gpr_timespec()> next_issue_;
   std::function<std::unique_ptr<grpc::ClientAsyncWriter<RequestType>>(
       BenchmarkService::Stub*, grpc::ClientContext*, ResponseType*,
-      CompletionQueue*, void*)>
-      start_req_;
+      CompletionQueue*)>
+      prepare_req_;
   grpc::Status status_;
   double start_;
   std::unique_ptr<grpc::ClientAsyncWriter<RequestType>> stream_;
 
   void StartInternal(CompletionQueue* cq) {
     cq_ = cq;
-    stream_ = start_req_(stub_, &context_, &response_, cq,
-                         ClientRpcContext::tag(this));
+    stream_ = prepare_req_(stub_, &context_, &response_, cq);
     next_state_ = State::STREAM_IDLE;
+    stream_->StartCall(ClientRpcContext::tag(this));
   }
 };
 
@@ -597,10 +574,10 @@ class AsyncStreamingFromClientClient final
 
  private:
   static void CheckDone(grpc::Status s, SimpleResponse* response) {}
-  static std::unique_ptr<grpc::ClientAsyncWriter<SimpleRequest>> StartReq(
+  static std::unique_ptr<grpc::ClientAsyncWriter<SimpleRequest>> PrepareReq(
       BenchmarkService::Stub* stub, grpc::ClientContext* ctx,
-      SimpleResponse* resp, CompletionQueue* cq, void* tag) {
-    auto stream = stub->AsyncStreamingFromClient(ctx, resp, cq, tag);
+      SimpleResponse* resp, CompletionQueue* cq) {
+    auto stream = stub->PrepareAsyncStreamingFromClient(ctx, resp, cq);
     return stream;
   };
   static ClientRpcContext* SetupCtx(BenchmarkService::Stub* stub,
@@ -608,7 +585,7 @@ class AsyncStreamingFromClientClient final
                                     const SimpleRequest& req) {
     return new ClientRpcContextStreamingFromClientImpl<SimpleRequest,
                                                        SimpleResponse>(
-        stub, req, next_issue, AsyncStreamingFromClientClient::StartReq,
+        stub, req, next_issue, AsyncStreamingFromClientClient::PrepareReq,
         AsyncStreamingFromClientClient::CheckDone);
   }
 };
@@ -621,8 +598,8 @@ class ClientRpcContextStreamingFromServerImpl : public ClientRpcContext {
       std::function<gpr_timespec()> next_issue,
       std::function<std::unique_ptr<grpc::ClientAsyncReader<ResponseType>>(
           BenchmarkService::Stub*, grpc::ClientContext*, const RequestType&,
-          CompletionQueue*, void*)>
-          start_req,
+          CompletionQueue*)>
+          prepare_req,
       std::function<void(grpc::Status, ResponseType*)> on_done)
       : context_(),
         stub_(stub),
@@ -632,7 +609,7 @@ class ClientRpcContextStreamingFromServerImpl : public ClientRpcContext {
         next_state_(State::INVALID),
         callback_(on_done),
         next_issue_(next_issue),
-        start_req_(start_req) {}
+        prepare_req_(prepare_req) {}
   ~ClientRpcContextStreamingFromServerImpl() override {}
   void Start(CompletionQueue* cq, const ClientConfig& config) override {
     StartInternal(cq);
@@ -664,8 +641,7 @@ class ClientRpcContextStreamingFromServerImpl : public ClientRpcContext {
   }
   void StartNewClone(CompletionQueue* cq) override {
     auto* clone = new ClientRpcContextStreamingFromServerImpl(
-        stub_, req_, next_issue_, start_req_, callback_);
-    std::lock_guard<ClientRpcContext> lclone(*clone);
+        stub_, req_, next_issue_, prepare_req_, callback_);
     clone->StartInternal(cq);
   }
 
@@ -682,8 +658,8 @@ class ClientRpcContextStreamingFromServerImpl : public ClientRpcContext {
   std::function<gpr_timespec()> next_issue_;
   std::function<std::unique_ptr<grpc::ClientAsyncReader<ResponseType>>(
       BenchmarkService::Stub*, grpc::ClientContext*, const RequestType&,
-      CompletionQueue*, void*)>
-      start_req_;
+      CompletionQueue*)>
+      prepare_req_;
   grpc::Status status_;
   double start_;
   std::unique_ptr<grpc::ClientAsyncReader<ResponseType>> stream_;
@@ -691,9 +667,9 @@ class ClientRpcContextStreamingFromServerImpl : public ClientRpcContext {
   void StartInternal(CompletionQueue* cq) {
     // TODO(vjpai): Add support to rate-pace this
     cq_ = cq;
+    stream_ = prepare_req_(stub_, &context_, req_, cq);
     next_state_ = State::STREAM_IDLE;
-    stream_ =
-        start_req_(stub_, &context_, req_, cq, ClientRpcContext::tag(this));
+    stream_->StartCall(ClientRpcContext::tag(this));
   }
 };
 
@@ -710,10 +686,10 @@ class AsyncStreamingFromServerClient final
 
  private:
   static void CheckDone(grpc::Status s, SimpleResponse* response) {}
-  static std::unique_ptr<grpc::ClientAsyncReader<SimpleResponse>> StartReq(
+  static std::unique_ptr<grpc::ClientAsyncReader<SimpleResponse>> PrepareReq(
       BenchmarkService::Stub* stub, grpc::ClientContext* ctx,
-      const SimpleRequest& req, CompletionQueue* cq, void* tag) {
-    auto stream = stub->AsyncStreamingFromServer(ctx, req, cq, tag);
+      const SimpleRequest& req, CompletionQueue* cq) {
+    auto stream = stub->PrepareAsyncStreamingFromServer(ctx, req, cq);
     return stream;
   };
   static ClientRpcContext* SetupCtx(BenchmarkService::Stub* stub,
@@ -721,7 +697,7 @@ class AsyncStreamingFromServerClient final
                                     const SimpleRequest& req) {
     return new ClientRpcContextStreamingFromServerImpl<SimpleRequest,
                                                        SimpleResponse>(
-        stub, req, next_issue, AsyncStreamingFromServerClient::StartReq,
+        stub, req, next_issue, AsyncStreamingFromServerClient::PrepareReq,
         AsyncStreamingFromServerClient::CheckDone);
   }
 };
@@ -733,8 +709,8 @@ class ClientRpcContextGenericStreamingImpl : public ClientRpcContext {
       std::function<gpr_timespec()> next_issue,
       std::function<std::unique_ptr<grpc::GenericClientAsyncReaderWriter>(
           grpc::GenericStub*, grpc::ClientContext*,
-          const grpc::string& method_name, CompletionQueue*, void*)>
-          start_req,
+          const grpc::string& method_name, CompletionQueue*)>
+          prepare_req,
       std::function<void(grpc::Status, ByteBuffer*)> on_done)
       : context_(),
         stub_(stub),
@@ -744,7 +720,7 @@ class ClientRpcContextGenericStreamingImpl : public ClientRpcContext {
         next_state_(State::INVALID),
         callback_(on_done),
         next_issue_(next_issue),
-        start_req_(start_req) {}
+        prepare_req_(prepare_req) {}
   ~ClientRpcContextGenericStreamingImpl() override {}
   void Start(CompletionQueue* cq, const ClientConfig& config) override {
     StartInternal(cq, config.messages_per_stream());
@@ -807,8 +783,7 @@ class ClientRpcContextGenericStreamingImpl : public ClientRpcContext {
   }
   void StartNewClone(CompletionQueue* cq) override {
     auto* clone = new ClientRpcContextGenericStreamingImpl(
-        stub_, req_, next_issue_, start_req_, callback_);
-    std::lock_guard<ClientRpcContext> lclone(*clone);
+        stub_, req_, next_issue_, prepare_req_, callback_);
     clone->StartInternal(cq, messages_per_stream_);
   }
 
@@ -834,8 +809,8 @@ class ClientRpcContextGenericStreamingImpl : public ClientRpcContext {
   std::function<gpr_timespec()> next_issue_;
   std::function<std::unique_ptr<grpc::GenericClientAsyncReaderWriter>(
       grpc::GenericStub*, grpc::ClientContext*, const grpc::string&,
-      CompletionQueue*, void*)>
-      start_req_;
+      CompletionQueue*)>
+      prepare_req_;
   grpc::Status status_;
   double start_;
   std::unique_ptr<grpc::GenericClientAsyncReaderWriter> stream_;
@@ -850,9 +825,9 @@ class ClientRpcContextGenericStreamingImpl : public ClientRpcContext {
         "/grpc.testing.BenchmarkService/StreamingCall");
     messages_per_stream_ = messages_per_stream;
     messages_issued_ = 0;
+    stream_ = prepare_req_(stub_, &context_, kMethodName, cq);
     next_state_ = State::STREAM_IDLE;
-    stream_ = start_req_(stub_, &context_, kMethodName, cq,
-                         ClientRpcContext::tag(this));
+    stream_->StartCall(ClientRpcContext::tag(this));
   }
 };
 
@@ -874,17 +849,17 @@ class GenericAsyncStreamingClient final
 
  private:
   static void CheckDone(grpc::Status s, ByteBuffer* response) {}
-  static std::unique_ptr<grpc::GenericClientAsyncReaderWriter> StartReq(
+  static std::unique_ptr<grpc::GenericClientAsyncReaderWriter> PrepareReq(
       grpc::GenericStub* stub, grpc::ClientContext* ctx,
-      const grpc::string& method_name, CompletionQueue* cq, void* tag) {
-    auto stream = stub->Call(ctx, method_name, cq, tag);
+      const grpc::string& method_name, CompletionQueue* cq) {
+    auto stream = stub->PrepareCall(ctx, method_name, cq);
     return stream;
   };
   static ClientRpcContext* SetupCtx(grpc::GenericStub* stub,
                                     std::function<gpr_timespec()> next_issue,
                                     const ByteBuffer& req) {
     return new ClientRpcContextGenericStreamingImpl(
-        stub, req, next_issue, GenericAsyncStreamingClient::StartReq,
+        stub, req, next_issue, GenericAsyncStreamingClient::PrepareReq,
         GenericAsyncStreamingClient::CheckDone);
   }
 };

From 05eadf21e05d521d73a05babf7c8f45218728355 Mon Sep 17 00:00:00 2001
From: Jan Tattermusch <jtattermusch@google.com>
Date: Mon, 11 Sep 2017 11:46:59 +0200
Subject: [PATCH 13/20] reveal leftover processes

---
 tools/internal_ci/linux/grpc_run_tests_matrix.sh    | 12 +++++++++++-
 tools/internal_ci/macos/grpc_run_tests_matrix.sh    |  5 +++++
 tools/internal_ci/windows/grpc_run_tests_matrix.bat | 10 ++++++----
 3 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/tools/internal_ci/linux/grpc_run_tests_matrix.sh b/tools/internal_ci/linux/grpc_run_tests_matrix.sh
index 028704b3ffe..bd1430b7415 100755
--- a/tools/internal_ci/linux/grpc_run_tests_matrix.sh
+++ b/tools/internal_ci/linux/grpc_run_tests_matrix.sh
@@ -20,4 +20,14 @@ cd $(dirname $0)/../../..
 
 source tools/internal_ci/helper_scripts/prepare_build_linux_rc
 
-tools/run_tests/run_tests_matrix.py $RUN_TESTS_FLAGS
+tools/run_tests/run_tests_matrix.py $RUN_TESTS_FLAGS || FAILED="true"
+
+# Reveal leftover processes that might be left behind by the build
+ps aux | grep -i kbuilder
+
+echo 'Exiting gRPC main test script.'
+
+if [ "$FAILED" != "" ]
+then
+  exit 1
+fi
diff --git a/tools/internal_ci/macos/grpc_run_tests_matrix.sh b/tools/internal_ci/macos/grpc_run_tests_matrix.sh
index 9a43e4869b0..8e7fd54a629 100755
--- a/tools/internal_ci/macos/grpc_run_tests_matrix.sh
+++ b/tools/internal_ci/macos/grpc_run_tests_matrix.sh
@@ -25,6 +25,11 @@ tools/run_tests/run_tests_matrix.py $RUN_TESTS_FLAGS || FAILED="true"
 # kill port_server.py to prevent the build from hanging
 ps aux | grep port_server\\.py | awk '{print $2}' | xargs kill -9
 
+# Reveal leftover processes that might be left behind by the build
+ps aux | grep -i kbuilder
+
+echo 'Exiting gRPC main test script.'
+
 if [ "$FAILED" != "" ]
 then
   exit 1
diff --git a/tools/internal_ci/windows/grpc_run_tests_matrix.bat b/tools/internal_ci/windows/grpc_run_tests_matrix.bat
index 08d834f8b06..10627add25c 100644
--- a/tools/internal_ci/windows/grpc_run_tests_matrix.bat
+++ b/tools/internal_ci/windows/grpc_run_tests_matrix.bat
@@ -17,8 +17,10 @@ cd /d %~dp0\..\..\..
 
 call tools/internal_ci/helper_scripts/prepare_build_windows.bat
 
-python tools/run_tests/run_tests_matrix.py %RUN_TESTS_FLAGS% || goto :error
-goto :EOF
+python tools/run_tests/run_tests_matrix.py %RUN_TESTS_FLAGS%
+set RUNTESTS_EXITCODE=%errorlevel%
 
-:error
-exit /b %errorlevel%
+@rem Reveal leftover processes that might be left behind by the build
+tasklist /V
+
+exit /b %RUNTESTS_EXITCODE%

From 8d3cc5ff0c2b86bd6766944891c1706153135a47 Mon Sep 17 00:00:00 2001
From: Nathaniel Manista <nathaniel@google.com>
Date: Fri, 15 Sep 2017 16:43:33 +0000
Subject: [PATCH 14/20] Clean up a few more uses of gRPC in _pb2.py files

Were this not done these would break when the default behavior of gRPC
Python Protoc Plug-In is changed to be the put-gRPC-code-elements-only-
in-_pb2_grpc.py-files behavior that currently happens only when the
grpc_2_0 flag is passed.
---
 .../protoc_plugin/_python_plugin_test.py      | 23 +++++++++++--------
 .../tests/qps/benchmark_server.py             |  6 ++---
 .../tests/stress/metrics_server.py            |  3 ++-
 3 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/src/python/grpcio_tests/tests/protoc_plugin/_python_plugin_test.py b/src/python/grpcio_tests/tests/protoc_plugin/_python_plugin_test.py
index 71493bfec63..5b84001aab3 100644
--- a/src/python/grpcio_tests/tests/protoc_plugin/_python_plugin_test.py
+++ b/src/python/grpcio_tests/tests/protoc_plugin/_python_plugin_test.py
@@ -33,7 +33,7 @@ from tests.unit.framework.common import test_constants
 import tests.protoc_plugin.protos.payload.test_payload_pb2 as payload_pb2
 import tests.protoc_plugin.protos.requests.r.test_requests_pb2 as request_pb2
 import tests.protoc_plugin.protos.responses.test_responses_pb2 as response_pb2
-import tests.protoc_plugin.protos.service.test_service_pb2 as service_pb2
+import tests.protoc_plugin.protos.service.test_service_pb2_grpc as service_pb2_grpc
 
 # Identifiers of entities we expect to find in the generated module.
 STUB_IDENTIFIER = 'TestServiceStub'
@@ -138,7 +138,7 @@ def _CreateService():
   """
     servicer_methods = _ServicerMethods()
 
-    class Servicer(getattr(service_pb2, SERVICER_IDENTIFIER)):
+    class Servicer(getattr(service_pb2_grpc, SERVICER_IDENTIFIER)):
 
         def UnaryCall(self, request, context):
             return servicer_methods.UnaryCall(request, context)
@@ -157,11 +157,12 @@ def _CreateService():
 
     server = grpc.server(
         futures.ThreadPoolExecutor(max_workers=test_constants.POOL_SIZE))
-    getattr(service_pb2, ADD_SERVICER_TO_SERVER_IDENTIFIER)(Servicer(), server)
+    getattr(service_pb2_grpc, ADD_SERVICER_TO_SERVER_IDENTIFIER)(Servicer(),
+                                                                 server)
     port = server.add_insecure_port('[::]:0')
     server.start()
     channel = grpc.insecure_channel('localhost:{}'.format(port))
-    stub = getattr(service_pb2, STUB_IDENTIFIER)(channel)
+    stub = getattr(service_pb2_grpc, STUB_IDENTIFIER)(channel)
     return _Service(servicer_methods, server, stub)
 
 
@@ -173,16 +174,17 @@ def _CreateIncompleteService():
       servicer_methods implements none of the methods required of it.
   """
 
-    class Servicer(getattr(service_pb2, SERVICER_IDENTIFIER)):
+    class Servicer(getattr(service_pb2_grpc, SERVICER_IDENTIFIER)):
         pass
 
     server = grpc.server(
         futures.ThreadPoolExecutor(max_workers=test_constants.POOL_SIZE))
-    getattr(service_pb2, ADD_SERVICER_TO_SERVER_IDENTIFIER)(Servicer(), server)
+    getattr(service_pb2_grpc, ADD_SERVICER_TO_SERVER_IDENTIFIER)(Servicer(),
+                                                                 server)
     port = server.add_insecure_port('[::]:0')
     server.start()
     channel = grpc.insecure_channel('localhost:{}'.format(port))
-    stub = getattr(service_pb2, STUB_IDENTIFIER)(channel)
+    stub = getattr(service_pb2_grpc, STUB_IDENTIFIER)(channel)
     return _Service(None, server, stub)
 
 
@@ -223,10 +225,11 @@ class PythonPluginTest(unittest.TestCase):
 
     def testImportAttributes(self):
         # check that we can access the generated module and its members.
-        self.assertIsNotNone(getattr(service_pb2, STUB_IDENTIFIER, None))
-        self.assertIsNotNone(getattr(service_pb2, SERVICER_IDENTIFIER, None))
+        self.assertIsNotNone(getattr(service_pb2_grpc, STUB_IDENTIFIER, None))
         self.assertIsNotNone(
-            getattr(service_pb2, ADD_SERVICER_TO_SERVER_IDENTIFIER, None))
+            getattr(service_pb2_grpc, SERVICER_IDENTIFIER, None))
+        self.assertIsNotNone(
+            getattr(service_pb2_grpc, ADD_SERVICER_TO_SERVER_IDENTIFIER, None))
 
     def testUpDown(self):
         service = _CreateService()
diff --git a/src/python/grpcio_tests/tests/qps/benchmark_server.py b/src/python/grpcio_tests/tests/qps/benchmark_server.py
index 05101fdc6db..bb078444912 100644
--- a/src/python/grpcio_tests/tests/qps/benchmark_server.py
+++ b/src/python/grpcio_tests/tests/qps/benchmark_server.py
@@ -13,10 +13,10 @@
 # limitations under the License.
 
 from src.proto.grpc.testing import messages_pb2
-from src.proto.grpc.testing import services_pb2
+from src.proto.grpc.testing import services_pb2_grpc
 
 
-class BenchmarkServer(services_pb2.BenchmarkServiceServicer):
+class BenchmarkServer(services_pb2_grpc.BenchmarkServiceServicer):
     """Synchronous Server implementation for the Benchmark service."""
 
     def UnaryCall(self, request, context):
@@ -29,7 +29,7 @@ class BenchmarkServer(services_pb2.BenchmarkServiceServicer):
             yield messages_pb2.SimpleResponse(payload=payload)
 
 
-class GenericBenchmarkServer(services_pb2.BenchmarkServiceServicer):
+class GenericBenchmarkServer(services_pb2_grpc.BenchmarkServiceServicer):
     """Generic Server implementation for the Benchmark service."""
 
     def __init__(self, resp_size):
diff --git a/src/python/grpcio_tests/tests/stress/metrics_server.py b/src/python/grpcio_tests/tests/stress/metrics_server.py
index 11ab6c3f4e9..33a74b4a388 100644
--- a/src/python/grpcio_tests/tests/stress/metrics_server.py
+++ b/src/python/grpcio_tests/tests/stress/metrics_server.py
@@ -16,11 +16,12 @@
 import time
 
 from src.proto.grpc.testing import metrics_pb2
+from src.proto.grpc.testing import metrics_pb2_grpc
 
 GAUGE_NAME = 'python_overall_qps'
 
 
-class MetricsServer(metrics_pb2.MetricsServiceServicer):
+class MetricsServer(metrics_pb2_grpc.MetricsServiceServicer):
 
     def __init__(self, histogram):
         self._start_time = time.time()

From 3fb250bdb16dda206596f28442502523e19bd2c4 Mon Sep 17 00:00:00 2001
From: Muxi Yan <mxyan@google.com>
Date: Fri, 15 Sep 2017 11:47:50 -0700
Subject: [PATCH 15/20] Polish output more

---
 src/objective-c/tests/run_tests.sh | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/src/objective-c/tests/run_tests.sh b/src/objective-c/tests/run_tests.sh
index 5b7a2d104aa..608ae6884b6 100755
--- a/src/objective-c/tests/run_tests.sh
+++ b/src/objective-c/tests/run_tests.sh
@@ -49,7 +49,8 @@ xcodebuild \
     HOST_PORT_REMOTE=grpc-test.sandbox.googleapis.com \
     test \
     | egrep -v "$XCODEBUILD_FILTER" \
-    | egrep -v '^$' -
+    | egrep -v '^$' \
+    | egrep -v "(GPBDictionary|GPBArray)" -
 
 echo "TIME:  $(date)"
 xcodebuild \
@@ -57,7 +58,8 @@ xcodebuild \
     -scheme CoreCronetEnd2EndTests \
     -destination name="iPhone 6" \
     test \
-    | egrep "$XCODEBUILD_FILTER" \
+    | egrep -v "$XCODEBUILD_FILTER" \
+    | egrep -v '^$' \
     | egrep -v "(GPBDictionary|GPBArray)" -
 
 echo "TIME:  $(date)"
@@ -65,7 +67,10 @@ xcodebuild \
     -workspace Tests.xcworkspace \
     -scheme CronetUnitTests \
     -destination name="iPhone 6" \
-    test | xcpretty
+    test \
+    | egrep -v "$XCODEBUILD_FILTER" \
+    | egrep -v '^$' \
+    | egrep -v "(GPBDictionary|GPBArray)" -
 
 echo "TIME:  $(date)"
 xcodebuild \
@@ -74,5 +79,6 @@ xcodebuild \
     -destination name="iPhone 6" \
     HOST_PORT_REMOTE=grpc-test.sandbox.googleapis.com \
     test \
-    | egrep "$XCODEBUILD_FILTER" \
+    | egrep -v "$XCODEBUILD_FILTER" \
+    | egrep -v '^$' \
     | egrep -v "(GPBDictionary|GPBArray)" -

From f68858464afd15402e09f480938e5efc6c7ff02f Mon Sep 17 00:00:00 2001
From: Matt Kwong <mattkwong@google.com>
Date: Mon, 21 Aug 2017 08:09:06 -0700
Subject: [PATCH 16/20] Add Kokoro perf PR jobs

---
 .../prepare_build_linux_perf_rc               | 15 +++++++
 .../linux/grpc_microbenchmark_diff.sh         | 38 +++++++++++++++++
 tools/internal_ci/linux/grpc_trickle_diff.sh  | 42 +++++++++++++++++++
 .../pull_request/grpc_microbenchmark_diff.cfg | 25 +++++++++++
 .../linux/pull_request/grpc_trickle_diff.cfg  | 25 +++++++++++
 5 files changed, 145 insertions(+)
 create mode 100755 tools/internal_ci/linux/grpc_microbenchmark_diff.sh
 create mode 100755 tools/internal_ci/linux/grpc_trickle_diff.sh
 create mode 100644 tools/internal_ci/linux/pull_request/grpc_microbenchmark_diff.cfg
 create mode 100644 tools/internal_ci/linux/pull_request/grpc_trickle_diff.cfg

diff --git a/tools/internal_ci/helper_scripts/prepare_build_linux_perf_rc b/tools/internal_ci/helper_scripts/prepare_build_linux_perf_rc
index 1b7779caa82..dc3c75a6a12 100644
--- a/tools/internal_ci/helper_scripts/prepare_build_linux_perf_rc
+++ b/tools/internal_ci/helper_scripts/prepare_build_linux_perf_rc
@@ -19,4 +19,19 @@
 ulimit -n 32768
 ulimit -c unlimited
 
+# Performance PR testing needs GH API key and PR metadata to comment results
+if [ -n "$KOKORO_GITHUB_PULL_REQUEST_NUMBER" ]; then
+  set +x
+  sudo apt-get install -y jq
+  export ghprbTargetBranch=$(curl -s https://api.github.com/repos/grpc/grpc/pulls/$KOKORO_GITHUB_PULL_REQUEST_NUMBER | jq -r .base.ref)
+
+  gsutil cp gs://grpc-testing-secrets/github_credentials/oauth_token.txt ~/
+  # TODO(matt-kwong): rename this to GITHUB_OAUTH_TOKEN after Jenkins deprecation
+  export JENKINS_OAUTH_TOKEN=$(cat ~/oauth_token.txt)
+  export ghprbPullId=$KOKORO_GITHUB_PULL_REQUEST_NUMBER
+  set -x
+fi
+
+sudo pip install tabulate
+
 git submodule update --init
diff --git a/tools/internal_ci/linux/grpc_microbenchmark_diff.sh b/tools/internal_ci/linux/grpc_microbenchmark_diff.sh
new file mode 100755
index 00000000000..58ffcf336b8
--- /dev/null
+++ b/tools/internal_ci/linux/grpc_microbenchmark_diff.sh
@@ -0,0 +1,38 @@
+#!/usr/bin/env bash
+# Copyright 2017 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# This script is invoked by Jenkins and runs a diff on the microbenchmarks
+set -ex
+
+# List of benchmarks that provide good signal for analyzing performance changes in pull requests
+BENCHMARKS_TO_RUN="bm_fullstack_unary_ping_pong bm_fullstack_streaming_ping_pong bm_fullstack_streaming_pump bm_closure bm_cq bm_call_create bm_error bm_chttp2_hpack bm_chttp2_transport bm_pollset bm_metadata"
+
+# Enter the gRPC repo root
+cd $(dirname $0)/../../..
+
+source tools/internal_ci/helper_scripts/prepare_build_linux_perf_rc
+
+tools/run_tests/start_port_server.py
+tools/jenkins/run_c_cpp_test.sh tools/profiling/microbenchmarks/bm_diff/bm_main.py \
+  -d origin/$ghprbTargetBranch \
+  -b $BENCHMARKS_TO_RUN || FAILED="true"
+
+# kill port_server.py to prevent the build from hanging
+ps aux | grep port_server\\.py | awk '{print $2}' | xargs kill -9
+
+if [ "$FAILED" != "" ]
+then
+  exit 1
+fi
diff --git a/tools/internal_ci/linux/grpc_trickle_diff.sh b/tools/internal_ci/linux/grpc_trickle_diff.sh
new file mode 100755
index 00000000000..624031afa78
--- /dev/null
+++ b/tools/internal_ci/linux/grpc_trickle_diff.sh
@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+# Copyright 2017 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# This script is invoked by Jenkins and runs a diff on the microbenchmarks
+set -ex
+
+# List of benchmarks that provide good signal for analyzing performance changes in pull requests
+BENCHMARKS_TO_RUN="cli_transport_stalls_per_iteration cli_stream_stalls_per_iteration svr_transport_stalls_per_iteration svr_stream_stalls_per_iteration"
+
+# Enter the gRPC repo root
+cd $(dirname $0)/../../..
+
+source tools/internal_ci/helper_scripts/prepare_build_linux_perf_rc
+
+tools/run_tests/start_port_server.py
+tools/jenkins/run_c_cpp_test.sh tools/profiling/microbenchmarks/bm_diff/bm_main.py \
+  -d origin/$ghprbTargetBranch \
+  -b bm_fullstack_trickle \
+  -l 4 \
+  -t $BENCHMARKS_TO_RUN \
+  --no-counters \
+  --pr_comment_name trickle || FAILED="true"
+
+# kill port_server.py to prevent the build from hanging
+ps aux | grep port_server\\.py | awk '{print $2}' | xargs kill -9
+
+if [ "$FAILED" != "" ]
+then
+  exit 1
+fi
diff --git a/tools/internal_ci/linux/pull_request/grpc_microbenchmark_diff.cfg b/tools/internal_ci/linux/pull_request/grpc_microbenchmark_diff.cfg
new file mode 100644
index 00000000000..9269c345f0a
--- /dev/null
+++ b/tools/internal_ci/linux/pull_request/grpc_microbenchmark_diff.cfg
@@ -0,0 +1,25 @@
+# Copyright 2017 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Config file for the internal CI (in protobuf text format)
+
+# Location of the continuous shell script in repository.
+build_file: "grpc/tools/internal_ci/linux/grpc_microbenchmark_diff.sh"
+timeout_mins: 120
+action {
+  define_artifacts {
+    regex: "**/*sponge_log.xml"
+    regex: "github/grpc/reports/**"
+  }
+}
diff --git a/tools/internal_ci/linux/pull_request/grpc_trickle_diff.cfg b/tools/internal_ci/linux/pull_request/grpc_trickle_diff.cfg
new file mode 100644
index 00000000000..e86b3ab4758
--- /dev/null
+++ b/tools/internal_ci/linux/pull_request/grpc_trickle_diff.cfg
@@ -0,0 +1,25 @@
+# Copyright 2017 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Config file for the internal CI (in protobuf text format)
+
+# Location of the continuous shell script in repository.
+build_file: "grpc/tools/internal_ci/linux/grpc_trickle_diff.sh"
+timeout_mins: 120
+action {
+  define_artifacts {
+    regex: "**/*sponge_log.xml"
+    regex: "github/grpc/reports/**"
+  }
+}

From 2795eae06eca4f649682f06099520fdedc7e215a Mon Sep 17 00:00:00 2001
From: Muxi Yan <mxyan@google.com>
Date: Sat, 16 Sep 2017 09:59:20 -0700
Subject: [PATCH 17/20] Fix timeout test

---
 src/objective-c/tests/GRPCClientTests.m | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/objective-c/tests/GRPCClientTests.m b/src/objective-c/tests/GRPCClientTests.m
index 4be3d1c5e87..82ac2600fab 100644
--- a/src/objective-c/tests/GRPCClientTests.m
+++ b/src/objective-c/tests/GRPCClientTests.m
@@ -28,6 +28,7 @@
 #import <RemoteTest/Messages.pbobjc.h>
 #import <RxLibrary/GRXWriteable.h>
 #import <RxLibrary/GRXWriter+Immediate.h>
+#import <RxLibrary/GRXBufferedPipe.h>
 
 #define TEST_TIMEOUT 16
 
@@ -39,6 +40,7 @@ static NSString * const kRemoteSSLHost = @"grpc-test.sandbox.googleapis.com";
 static GRPCProtoMethod *kInexistentMethod;
 static GRPCProtoMethod *kEmptyCallMethod;
 static GRPCProtoMethod *kUnaryCallMethod;
+static GRPCProtoMethod *kFullDuplexCallMethod;
 
 /** Observer class for testing that responseMetadata is KVO-compliant */
 @interface PassthroughObserver : NSObject
@@ -106,6 +108,9 @@ static GRPCProtoMethod *kUnaryCallMethod;
   kUnaryCallMethod = [[GRPCProtoMethod alloc] initWithPackage:kPackage
                                                       service:kService
                                                        method:@"UnaryCall"];
+  kFullDuplexCallMethod = [[GRPCProtoMethod alloc] initWithPackage:kPackage
+                                                           service:kService
+                                                            method:@"FullDuplexCall"];
 }
 
 - (void)testConnectionToRemoteServer {
@@ -423,11 +428,12 @@ static GRPCProtoMethod *kUnaryCallMethod;
 }
 
 - (void)testTimeout {
-  __weak XCTestExpectation *completion = [self expectationWithDescription:@"Empty RPC completed."];
+  __weak XCTestExpectation *completion = [self expectationWithDescription:@"RPC completed."];
 
+  GRXBufferedPipe *pipe = [GRXBufferedPipe pipe];
   GRPCCall *call = [[GRPCCall alloc] initWithHost:kHostAddress
-                                             path:kEmptyCallMethod.HTTPPath
-                                   requestsWriter:[GRXWriter writerWithValue:[NSData data]]];
+                                             path:kFullDuplexCallMethod.HTTPPath
+                                   requestsWriter:pipe];
 
   id<GRXWriteable> responsesWriteable = [[GRXWriteable alloc] initWithValueHandler:^(NSData *value) {
     XCTAssert(0, @"Failure: response received; Expect: no response received.");

From 44038eb9b630eafad57e30e09d021de8d68e94d5 Mon Sep 17 00:00:00 2001
From: Nathaniel Manista <nathaniel@google.com>
Date: Sat, 16 Sep 2017 16:13:09 +0000
Subject: [PATCH 18/20] Tweak Python sanity test

 - Move it out of the "unit" package, as it's not itself a unit test.

 - Suffix the test class with "Test" as we do with every other subclass
   of unittest.TestCase.

 - Add a larger-than-we'll-need-any-time-soon maxDiff so that failures
   are fully described.

 - Relax the assertion from assertListEqual to assertSequenceEqual
   since we don't actually care whether or not the sequences being
   compared are list instances.

 - Change the order of the assertions arguments to match the
   "<expected>, <actual>" convention used in our assert*Equal calls
   elsewhere throughout the test corpus.

 - Internal implementation simplifications.
---
 .../tests/{unit => }/_sanity/__init__.py        |  0
 .../tests/{unit => }/_sanity/_sanity_test.py    | 17 +++++++++--------
 src/python/grpcio_tests/tests/tests.json        |  2 +-
 3 files changed, 10 insertions(+), 9 deletions(-)
 rename src/python/grpcio_tests/tests/{unit => }/_sanity/__init__.py (100%)
 rename src/python/grpcio_tests/tests/{unit => }/_sanity/_sanity_test.py (78%)

diff --git a/src/python/grpcio_tests/tests/unit/_sanity/__init__.py b/src/python/grpcio_tests/tests/_sanity/__init__.py
similarity index 100%
rename from src/python/grpcio_tests/tests/unit/_sanity/__init__.py
rename to src/python/grpcio_tests/tests/_sanity/__init__.py
diff --git a/src/python/grpcio_tests/tests/unit/_sanity/_sanity_test.py b/src/python/grpcio_tests/tests/_sanity/_sanity_test.py
similarity index 78%
rename from src/python/grpcio_tests/tests/unit/_sanity/_sanity_test.py
rename to src/python/grpcio_tests/tests/_sanity/_sanity_test.py
index 19bc8801ebc..b4079850ff7 100644
--- a/src/python/grpcio_tests/tests/unit/_sanity/_sanity_test.py
+++ b/src/python/grpcio_tests/tests/_sanity/_sanity_test.py
@@ -21,24 +21,25 @@ import six
 import tests
 
 
-class Sanity(unittest.TestCase):
+class SanityTest(unittest.TestCase):
+
+    maxDiff = 32768
 
     def testTestsJsonUpToDate(self):
         """Autodiscovers all test suites and checks that tests.json is up to date"""
         loader = tests.Loader()
         loader.loadTestsFromNames(['tests'])
-        test_suite_names = [
+        test_suite_names = sorted({
             test_case_class.id().rsplit('.', 1)[0]
             for test_case_class in tests._loader.iterate_suite_cases(
                 loader.suite)
-        ]
-        test_suite_names = sorted(set(test_suite_names))
+        })
 
         tests_json_string = pkg_resources.resource_string('tests', 'tests.json')
-        if six.PY3:
-            tests_json_string = tests_json_string.decode()
-        tests_json = json.loads(tests_json_string)
-        self.assertListEqual(test_suite_names, tests_json)
+        tests_json = json.loads(tests_json_string.decode()
+                                if six.PY3 else tests_json_string)
+
+        self.assertSequenceEqual(tests_json, test_suite_names)
 
 
 if __name__ == '__main__':
diff --git a/src/python/grpcio_tests/tests/tests.json b/src/python/grpcio_tests/tests/tests.json
index 4c078e6c22b..a3f2a9d8206 100644
--- a/src/python/grpcio_tests/tests/tests.json
+++ b/src/python/grpcio_tests/tests/tests.json
@@ -1,4 +1,5 @@
 [
+  "_sanity._sanity_test.SanityTest",
   "health_check._health_servicer_test.HealthServicerTest",
   "interop._insecure_intraop_test.InsecureIntraopTest",
   "interop._secure_intraop_test.SecureIntraopTest",
@@ -41,7 +42,6 @@
   "unit._reconnect_test.ReconnectTest",
   "unit._resource_exhausted_test.ResourceExhaustedTest",
   "unit._rpc_test.RPCTest",
-  "unit._sanity._sanity_test.Sanity",
   "unit._thread_cleanup_test.CleanupThreadTest",
   "unit.beta._beta_features_test.BetaFeaturesTest",
   "unit.beta._beta_features_test.ContextManagementAndLifecycleTest",

From 719ade3cdcb5e132087fa8a443f1735adfe05634 Mon Sep 17 00:00:00 2001
From: Nathaniel Manista <nathaniel@google.com>
Date: Sat, 16 Sep 2017 15:28:22 +0000
Subject: [PATCH 19/20] Overhaul protoc_plugins._split_definitions_test

We were mistaken before when we were testing _pb2.py files being
generated in one directory and _pb2_grpc.py files being generated in
another directory. Sure, that was a thing our code generator could do,
but because of the way paths and packages work in Python it wasn't a
realistic use case for actual users.

This test now tests _pb2.py files and _pb2_grpc.py files being
generated either together or independently of one another, and if
independently, in either order. Looking forward to an eventual
py_grpc_library Bazel rule, that's what actually matters.
---
 .../protoc_plugin/_split_definitions_test.py  | 519 +++++++++---------
 .../split_messages/__init__.py                |  13 -
 .../split_messages/{ => sub}/messages.proto   |   0
 .../split_services/__init__.py                |  13 -
 src/python/grpcio_tests/tests/tests.json      |  12 +-
 5 files changed, 263 insertions(+), 294 deletions(-)
 delete mode 100644 src/python/grpcio_tests/tests/protoc_plugin/protos/invocation_testing/split_messages/__init__.py
 rename src/python/grpcio_tests/tests/protoc_plugin/protos/invocation_testing/split_messages/{ => sub}/messages.proto (100%)
 delete mode 100644 src/python/grpcio_tests/tests/protoc_plugin/protos/invocation_testing/split_services/__init__.py

diff --git a/src/python/grpcio_tests/tests/protoc_plugin/_split_definitions_test.py b/src/python/grpcio_tests/tests/protoc_plugin/_split_definitions_test.py
index 1aeb62a7c5c..7868cdbfb31 100644
--- a/src/python/grpcio_tests/tests/protoc_plugin/_split_definitions_test.py
+++ b/src/python/grpcio_tests/tests/protoc_plugin/_split_definitions_test.py
@@ -12,22 +12,20 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import collections
+import abc
 from concurrent import futures
 import contextlib
-import distutils.spawn
-import errno
 import importlib
 import os
-import os.path
+from os import path
 import pkgutil
+import platform
 import shutil
-import subprocess
 import sys
 import tempfile
-import threading
 import unittest
-import platform
+
+import six
 
 import grpc
 from grpc_tools import protoc
@@ -37,292 +35,285 @@ _MESSAGES_IMPORT = b'import "messages.proto";'
 _SPLIT_NAMESPACE = b'package grpc_protoc_plugin.invocation_testing.split;'
 _COMMON_NAMESPACE = b'package grpc_protoc_plugin.invocation_testing;'
 
+_RELATIVE_PROTO_PATH = 'relative_proto_path'
+_RELATIVE_PYTHON_OUT = 'relative_python_out'
+
 
 @contextlib.contextmanager
-def _system_path(path):
+def _system_path(path_insertion):
     old_system_path = sys.path[:]
-    sys.path = sys.path[0:1] + path + sys.path[1:]
+    sys.path = sys.path[0:1] + path_insertion + sys.path[1:]
     yield
     sys.path = old_system_path
 
 
-class DummySplitServicer(object):
+# NOTE(nathaniel): https://twitter.com/exoplaneteer/status/677259364256747520
+# Life lesson "just always default to idempotence" reinforced.
+def _create_directory_tree(root, path_components_sequence):
+    created = set()
+    for path_components in path_components_sequence:
+        thus_far = ''
+        for path_component in path_components:
+            relative_path = path.join(thus_far, path_component)
+            if relative_path not in created:
+                os.makedirs(path.join(root, relative_path))
+                created.add(relative_path)
+            thus_far = path.join(thus_far, path_component)
+
+
+def _massage_proto_content(proto_content, test_name_bytes,
+                           messages_proto_relative_file_name_bytes):
+    package_substitution = (b'package grpc_protoc_plugin.invocation_testing.' +
+                            test_name_bytes + b';')
+    common_namespace_substituted = proto_content.replace(_COMMON_NAMESPACE,
+                                                         package_substitution)
+    split_namespace_substituted = common_namespace_substituted.replace(
+        _SPLIT_NAMESPACE, package_substitution)
+    message_import_replaced = split_namespace_substituted.replace(
+        _MESSAGES_IMPORT,
+        b'import "' + messages_proto_relative_file_name_bytes + b'";')
+    return message_import_replaced
+
+
+def _packagify(directory):
+    for subdirectory, _, _ in os.walk(directory):
+        init_file_name = path.join(subdirectory, '__init__.py')
+        with open(init_file_name, 'wb') as init_file:
+            init_file.write(b'')
 
-    def __init__(self, request_class, response_class):
-        self.request_class = request_class
-        self.response_class = response_class
+
+class _Servicer(object):
+
+    def __init__(self, response_class):
+        self._response_class = response_class
 
     def Call(self, request, context):
-        return self.response_class()
+        return self._response_class()
 
 
-class SeparateTestMixin(object):
+def _protoc(proto_path, python_out, grpc_python_out_flag, grpc_python_out,
+            absolute_proto_file_names):
+    args = [
+        '',
+        '--proto_path={}'.format(proto_path),
+    ]
+    if python_out is not None:
+        args.append('--python_out={}'.format(python_out))
+    if grpc_python_out is not None:
+        args.append('--grpc_python_out={}:{}'.format(grpc_python_out_flag,
+                                                     grpc_python_out))
+    args.extend(absolute_proto_file_names)
+    return protoc.main(args)
 
-    def testImportAttributes(self):
-        with _system_path([self.python_out_directory]):
-            pb2 = importlib.import_module(self.pb2_import)
-        pb2.Request
-        pb2.Response
-        if self.should_find_services_in_pb2:
-            pb2.TestServiceServicer
-        else:
-            with self.assertRaises(AttributeError):
-                pb2.TestServiceServicer
-
-        with _system_path([self.grpc_python_out_directory]):
-            pb2_grpc = importlib.import_module(self.pb2_grpc_import)
-        pb2_grpc.TestServiceServicer
-        with self.assertRaises(AttributeError):
-            pb2_grpc.Request
-        with self.assertRaises(AttributeError):
-            pb2_grpc.Response
-
-    def testCall(self):
-        with _system_path([self.python_out_directory]):
-            pb2 = importlib.import_module(self.pb2_import)
-        with _system_path([self.grpc_python_out_directory]):
-            pb2_grpc = importlib.import_module(self.pb2_grpc_import)
-        server = grpc.server(
-            futures.ThreadPoolExecutor(max_workers=test_constants.POOL_SIZE))
-        pb2_grpc.add_TestServiceServicer_to_server(
-            DummySplitServicer(pb2.Request, pb2.Response), server)
-        port = server.add_insecure_port('[::]:0')
-        server.start()
-        channel = grpc.insecure_channel('localhost:{}'.format(port))
-        stub = pb2_grpc.TestServiceStub(channel)
-        request = pb2.Request()
-        expected_response = pb2.Response()
-        response = stub.Call(request)
-        self.assertEqual(expected_response, response)
-
-
-class CommonTestMixin(object):
-
-    def testImportAttributes(self):
-        with _system_path([self.python_out_directory]):
-            pb2 = importlib.import_module(self.pb2_import)
-        pb2.Request
-        pb2.Response
-        if self.should_find_services_in_pb2:
-            pb2.TestServiceServicer
-        else:
-            with self.assertRaises(AttributeError):
-                pb2.TestServiceServicer
-
-        with _system_path([self.grpc_python_out_directory]):
-            pb2_grpc = importlib.import_module(self.pb2_grpc_import)
-        pb2_grpc.TestServiceServicer
-        with self.assertRaises(AttributeError):
-            pb2_grpc.Request
-        with self.assertRaises(AttributeError):
-            pb2_grpc.Response
-
-    def testCall(self):
-        with _system_path([self.python_out_directory]):
-            pb2 = importlib.import_module(self.pb2_import)
-        with _system_path([self.grpc_python_out_directory]):
-            pb2_grpc = importlib.import_module(self.pb2_grpc_import)
-        server = grpc.server(
-            futures.ThreadPoolExecutor(max_workers=test_constants.POOL_SIZE))
-        pb2_grpc.add_TestServiceServicer_to_server(
-            DummySplitServicer(pb2.Request, pb2.Response), server)
-        port = server.add_insecure_port('[::]:0')
-        server.start()
-        channel = grpc.insecure_channel('localhost:{}'.format(port))
-        stub = pb2_grpc.TestServiceStub(channel)
-        request = pb2.Request()
-        expected_response = pb2.Response()
-        response = stub.Call(request)
-        self.assertEqual(expected_response, response)
-
-
-@unittest.skipIf(platform.python_implementation() == "PyPy",
-                 "Skip test if run with PyPy")
-class SameSeparateTest(unittest.TestCase, SeparateTestMixin):
 
-    def setUp(self):
-        same_proto_contents = pkgutil.get_data(
-            'tests.protoc_plugin.protos.invocation_testing', 'same.proto')
-        self.directory = tempfile.mkdtemp(suffix='same_separate', dir='.')
-        self.proto_directory = os.path.join(self.directory, 'proto_path')
-        self.python_out_directory = os.path.join(self.directory, 'python_out')
-        self.grpc_python_out_directory = os.path.join(self.directory,
-                                                      'grpc_python_out')
-        os.makedirs(self.proto_directory)
-        os.makedirs(self.python_out_directory)
-        os.makedirs(self.grpc_python_out_directory)
-        same_proto_file = os.path.join(self.proto_directory,
-                                       'same_separate.proto')
-        open(same_proto_file, 'wb').write(
-            same_proto_contents.replace(
-                _COMMON_NAMESPACE,
-                b'package grpc_protoc_plugin.invocation_testing.same_separate;'))
-        protoc_result = protoc.main([
-            '',
-            '--proto_path={}'.format(self.proto_directory),
-            '--python_out={}'.format(self.python_out_directory),
-            '--grpc_python_out=grpc_2_0:{}'.format(
-                self.grpc_python_out_directory),
-            same_proto_file,
-        ])
-        if protoc_result != 0:
-            raise Exception("unexpected protoc error")
-        open(os.path.join(self.grpc_python_out_directory, '__init__.py'),
-             'w').write('')
-        open(os.path.join(self.python_out_directory, '__init__.py'),
-             'w').write('')
-        self.pb2_import = 'same_separate_pb2'
-        self.pb2_grpc_import = 'same_separate_pb2_grpc'
-        self.should_find_services_in_pb2 = False
+class _Mid2016ProtocStyle(object):
 
-    def tearDown(self):
-        shutil.rmtree(self.directory)
+    def name(self):
+        return 'Mid2016ProtocStyle'
 
+    def grpc_in_pb2_expected(self):
+        return True
 
-@unittest.skipIf(platform.python_implementation() == "PyPy",
-                 "Skip test if run with PyPy")
-class SameCommonTest(unittest.TestCase, CommonTestMixin):
+    def protoc(self, proto_path, python_out, absolute_proto_file_names):
+        return (_protoc(proto_path, python_out, 'grpc_1_0', python_out,
+                        absolute_proto_file_names),)
 
-    def setUp(self):
-        same_proto_contents = pkgutil.get_data(
-            'tests.protoc_plugin.protos.invocation_testing', 'same.proto')
-        self.directory = tempfile.mkdtemp(suffix='same_common', dir='.')
-        self.proto_directory = os.path.join(self.directory, 'proto_path')
-        self.python_out_directory = os.path.join(self.directory, 'python_out')
-        self.grpc_python_out_directory = self.python_out_directory
-        os.makedirs(self.proto_directory)
-        os.makedirs(self.python_out_directory)
-        same_proto_file = os.path.join(self.proto_directory,
-                                       'same_common.proto')
-        open(same_proto_file, 'wb').write(
-            same_proto_contents.replace(
-                _COMMON_NAMESPACE,
-                b'package grpc_protoc_plugin.invocation_testing.same_common;'))
-
-        protoc_result = protoc.main([
-            '',
-            '--proto_path={}'.format(self.proto_directory),
-            '--python_out={}'.format(self.python_out_directory),
-            '--grpc_python_out={}'.format(self.grpc_python_out_directory),
-            same_proto_file,
-        ])
-        if protoc_result != 0:
-            raise Exception("unexpected protoc error")
-        open(os.path.join(self.python_out_directory, '__init__.py'),
-             'w').write('')
-        self.pb2_import = 'same_common_pb2'
-        self.pb2_grpc_import = 'same_common_pb2_grpc'
-        self.should_find_services_in_pb2 = True
 
-    def tearDown(self):
-        shutil.rmtree(self.directory)
+class _SingleProtocExecutionProtocStyle(object):
 
+    def name(self):
+        return 'SingleProtocExecutionProtocStyle'
 
-@unittest.skipIf(platform.python_implementation() == "PyPy",
-                 "Skip test if run with PyPy")
-class SplitCommonTest(unittest.TestCase, CommonTestMixin):
+    def grpc_in_pb2_expected(self):
+        return False
 
-    def setUp(self):
-        services_proto_contents = pkgutil.get_data(
-            'tests.protoc_plugin.protos.invocation_testing.split_services',
-            'services.proto')
-        messages_proto_contents = pkgutil.get_data(
-            'tests.protoc_plugin.protos.invocation_testing.split_messages',
-            'messages.proto')
-        self.directory = tempfile.mkdtemp(suffix='split_common', dir='.')
-        self.proto_directory = os.path.join(self.directory, 'proto_path')
-        self.python_out_directory = os.path.join(self.directory, 'python_out')
-        self.grpc_python_out_directory = self.python_out_directory
-        os.makedirs(self.proto_directory)
-        os.makedirs(self.python_out_directory)
-        services_proto_file = os.path.join(self.proto_directory,
-                                           'split_common_services.proto')
-        messages_proto_file = os.path.join(self.proto_directory,
-                                           'split_common_messages.proto')
-        open(services_proto_file, 'wb').write(
-            services_proto_contents.replace(
-                _MESSAGES_IMPORT, b'import "split_common_messages.proto";')
-            .replace(
-                _SPLIT_NAMESPACE,
-                b'package grpc_protoc_plugin.invocation_testing.split_common;'))
-        open(messages_proto_file, 'wb').write(
-            messages_proto_contents.replace(
-                _SPLIT_NAMESPACE,
-                b'package grpc_protoc_plugin.invocation_testing.split_common;'))
-        protoc_result = protoc.main([
-            '',
-            '--proto_path={}'.format(self.proto_directory),
-            '--python_out={}'.format(self.python_out_directory),
-            '--grpc_python_out={}'.format(self.grpc_python_out_directory),
-            services_proto_file,
-            messages_proto_file,
-        ])
-        if protoc_result != 0:
-            raise Exception("unexpected protoc error")
-        open(os.path.join(self.python_out_directory, '__init__.py'),
-             'w').write('')
-        self.pb2_import = 'split_common_messages_pb2'
-        self.pb2_grpc_import = 'split_common_services_pb2_grpc'
-        self.should_find_services_in_pb2 = False
+    def protoc(self, proto_path, python_out, absolute_proto_file_names):
+        return (_protoc(proto_path, python_out, 'grpc_2_0', python_out,
+                        absolute_proto_file_names),)
+
+
+class _ProtoBeforeGrpcProtocStyle(object):
+
+    def name(self):
+        return 'ProtoBeforeGrpcProtocStyle'
+
+    def grpc_in_pb2_expected(self):
+        return False
+
+    def protoc(self, proto_path, python_out, absolute_proto_file_names):
+        pb2_protoc_exit_code = _protoc(proto_path, python_out, None, None,
+                                       absolute_proto_file_names)
+        pb2_grpc_protoc_exit_code = _protoc(
+            proto_path, None, 'grpc_2_0', python_out, absolute_proto_file_names)
+        return pb2_protoc_exit_code, pb2_grpc_protoc_exit_code,
 
-    def tearDown(self):
-        shutil.rmtree(self.directory)
 
+class _GrpcBeforeProtoProtocStyle(object):
 
-@unittest.skipIf(platform.python_implementation() == "PyPy",
-                 "Skip test if run with PyPy")
-class SplitSeparateTest(unittest.TestCase, SeparateTestMixin):
+    def name(self):
+        return 'GrpcBeforeProtoProtocStyle'
+
+    def grpc_in_pb2_expected(self):
+        return False
+
+    def protoc(self, proto_path, python_out, absolute_proto_file_names):
+        pb2_grpc_protoc_exit_code = _protoc(
+            proto_path, None, 'grpc_2_0', python_out, absolute_proto_file_names)
+        pb2_protoc_exit_code = _protoc(proto_path, python_out, None, None,
+                                       absolute_proto_file_names)
+        return pb2_grpc_protoc_exit_code, pb2_protoc_exit_code,
+
+
+_PROTOC_STYLES = (_Mid2016ProtocStyle(), _SingleProtocExecutionProtocStyle(),
+                  _ProtoBeforeGrpcProtocStyle(), _GrpcBeforeProtoProtocStyle(),)
+
+
+@unittest.skipIf(platform.python_implementation() == 'PyPy',
+                 'Skip test if run with PyPy!')
+class _Test(six.with_metaclass(abc.ABCMeta, unittest.TestCase)):
 
     def setUp(self):
-        services_proto_contents = pkgutil.get_data(
-            'tests.protoc_plugin.protos.invocation_testing.split_services',
-            'services.proto')
-        messages_proto_contents = pkgutil.get_data(
-            'tests.protoc_plugin.protos.invocation_testing.split_messages',
-            'messages.proto')
-        self.directory = tempfile.mkdtemp(suffix='split_separate', dir='.')
-        self.proto_directory = os.path.join(self.directory, 'proto_path')
-        self.python_out_directory = os.path.join(self.directory, 'python_out')
-        self.grpc_python_out_directory = os.path.join(self.directory,
-                                                      'grpc_python_out')
-        os.makedirs(self.proto_directory)
-        os.makedirs(self.python_out_directory)
-        os.makedirs(self.grpc_python_out_directory)
-        services_proto_file = os.path.join(self.proto_directory,
-                                           'split_separate_services.proto')
-        messages_proto_file = os.path.join(self.proto_directory,
-                                           'split_separate_messages.proto')
-        open(services_proto_file, 'wb').write(
-            services_proto_contents.replace(
-                _MESSAGES_IMPORT, b'import "split_separate_messages.proto";')
-            .replace(
-                _SPLIT_NAMESPACE,
-                b'package grpc_protoc_plugin.invocation_testing.split_separate;'
-            ))
-        open(messages_proto_file, 'wb').write(
-            messages_proto_contents.replace(
-                _SPLIT_NAMESPACE,
-                b'package grpc_protoc_plugin.invocation_testing.split_separate;'
-            ))
-        protoc_result = protoc.main([
-            '',
-            '--proto_path={}'.format(self.proto_directory),
-            '--python_out={}'.format(self.python_out_directory),
-            '--grpc_python_out=grpc_2_0:{}'.format(
-                self.grpc_python_out_directory),
-            services_proto_file,
-            messages_proto_file,
-        ])
-        if protoc_result != 0:
-            raise Exception("unexpected protoc error")
-        open(os.path.join(self.python_out_directory, '__init__.py'),
-             'w').write('')
-        self.pb2_import = 'split_separate_messages_pb2'
-        self.pb2_grpc_import = 'split_separate_services_pb2_grpc'
-        self.should_find_services_in_pb2 = False
+        self._directory = tempfile.mkdtemp(suffix=self.NAME, dir='.')
+        self._proto_path = path.join(self._directory, _RELATIVE_PROTO_PATH)
+        self._python_out = path.join(self._directory, _RELATIVE_PYTHON_OUT)
+
+        os.makedirs(self._proto_path)
+        os.makedirs(self._python_out)
+
+        proto_directories_and_names = {
+            (self.MESSAGES_PROTO_RELATIVE_DIRECTORY_NAMES,
+             self.MESSAGES_PROTO_FILE_NAME,),
+            (self.SERVICES_PROTO_RELATIVE_DIRECTORY_NAMES,
+             self.SERVICES_PROTO_FILE_NAME,),
+        }
+        messages_proto_relative_file_name_forward_slashes = '/'.join(
+            self.MESSAGES_PROTO_RELATIVE_DIRECTORY_NAMES + (
+                self.MESSAGES_PROTO_FILE_NAME,))
+        _create_directory_tree(self._proto_path, (
+            relative_proto_directory_names
+            for relative_proto_directory_names, _ in proto_directories_and_names
+        ))
+        self._absolute_proto_file_names = set()
+        for relative_directory_names, file_name in proto_directories_and_names:
+            absolute_proto_file_name = path.join(
+                self._proto_path, *relative_directory_names + (file_name,))
+            raw_proto_content = pkgutil.get_data(
+                'tests.protoc_plugin.protos.invocation_testing',
+                path.join(*relative_directory_names + (file_name,)))
+            massaged_proto_content = _massage_proto_content(
+                raw_proto_content,
+                self.NAME.encode(),
+                messages_proto_relative_file_name_forward_slashes.encode())
+            with open(absolute_proto_file_name, 'wb') as proto_file:
+                proto_file.write(massaged_proto_content)
+            self._absolute_proto_file_names.add(absolute_proto_file_name)
 
     def tearDown(self):
-        shutil.rmtree(self.directory)
+        shutil.rmtree(self._directory)
+
+    def _protoc(self):
+        protoc_exit_codes = self.PROTOC_STYLE.protoc(
+            self._proto_path, self._python_out, self._absolute_proto_file_names)
+        for protoc_exit_code in protoc_exit_codes:
+            self.assertEqual(0, protoc_exit_code)
+
+        _packagify(self._python_out)
+
+        generated_modules = {}
+        expected_generated_full_module_names = {
+            self.EXPECTED_MESSAGES_PB2,
+            self.EXPECTED_SERVICES_PB2,
+            self.EXPECTED_SERVICES_PB2_GRPC,
+        }
+        with _system_path([self._python_out]):
+            for full_module_name in expected_generated_full_module_names:
+                module = importlib.import_module(full_module_name)
+                generated_modules[full_module_name] = module
+
+        self._messages_pb2 = generated_modules[self.EXPECTED_MESSAGES_PB2]
+        self._services_pb2 = generated_modules[self.EXPECTED_SERVICES_PB2]
+        self._services_pb2_grpc = generated_modules[
+            self.EXPECTED_SERVICES_PB2_GRPC]
+
+    def _services_modules(self):
+        if self.PROTOC_STYLE.grpc_in_pb2_expected():
+            return self._services_pb2, self._services_pb2_grpc,
+        else:
+            return self._services_pb2_grpc,
+
+    def test_imported_attributes(self):
+        self._protoc()
+
+        self._messages_pb2.Request
+        self._messages_pb2.Response
+        self._services_pb2.DESCRIPTOR.services_by_name['TestService']
+        for services_module in self._services_modules():
+            services_module.TestServiceStub
+            services_module.TestServiceServicer
+            services_module.add_TestServiceServicer_to_server
+
+    def test_call(self):
+        self._protoc()
+
+        for services_module in self._services_modules():
+            server = grpc.server(
+                futures.ThreadPoolExecutor(
+                    max_workers=test_constants.POOL_SIZE))
+            services_module.add_TestServiceServicer_to_server(
+                _Servicer(self._messages_pb2.Response), server)
+            port = server.add_insecure_port('[::]:0')
+            server.start()
+            channel = grpc.insecure_channel('localhost:{}'.format(port))
+            stub = services_module.TestServiceStub(channel)
+            response = stub.Call(self._messages_pb2.Request())
+            self.assertEqual(self._messages_pb2.Response(), response)
+
+
+def _create_test_case_class(split_proto, protoc_style):
+    attributes = {}
+
+    name = '{}{}'.format('SplitProto' if split_proto else 'SameProto',
+                         protoc_style.name())
+    attributes['NAME'] = name
+
+    if split_proto:
+        attributes['MESSAGES_PROTO_RELATIVE_DIRECTORY_NAMES'] = (
+            'split_messages', 'sub',)
+        attributes['MESSAGES_PROTO_FILE_NAME'] = 'messages.proto'
+        attributes['SERVICES_PROTO_RELATIVE_DIRECTORY_NAMES'] = (
+            'split_services',)
+        attributes['SERVICES_PROTO_FILE_NAME'] = 'services.proto'
+        attributes['EXPECTED_MESSAGES_PB2'] = 'split_messages.sub.messages_pb2'
+        attributes['EXPECTED_SERVICES_PB2'] = 'split_services.services_pb2'
+        attributes['EXPECTED_SERVICES_PB2_GRPC'] = (
+            'split_services.services_pb2_grpc')
+    else:
+        attributes['MESSAGES_PROTO_RELATIVE_DIRECTORY_NAMES'] = ()
+        attributes['MESSAGES_PROTO_FILE_NAME'] = 'same.proto'
+        attributes['SERVICES_PROTO_RELATIVE_DIRECTORY_NAMES'] = ()
+        attributes['SERVICES_PROTO_FILE_NAME'] = 'same.proto'
+        attributes['EXPECTED_MESSAGES_PB2'] = 'same_pb2'
+        attributes['EXPECTED_SERVICES_PB2'] = 'same_pb2'
+        attributes['EXPECTED_SERVICES_PB2_GRPC'] = 'same_pb2_grpc'
+
+    attributes['PROTOC_STYLE'] = protoc_style
+
+    attributes['__module__'] = _Test.__module__
+
+    return type('{}Test'.format(name), (_Test,), attributes)
+
+
+def _create_test_case_classes():
+    for split_proto in (False, True,):
+        for protoc_style in _PROTOC_STYLES:
+            yield _create_test_case_class(split_proto, protoc_style)
+
+
+def load_tests(loader, tests, pattern):
+    tests = tuple(
+        loader.loadTestsFromTestCase(test_case_class)
+        for test_case_class in _create_test_case_classes())
+    return unittest.TestSuite(tests=tests)
 
 
 if __name__ == '__main__':
diff --git a/src/python/grpcio_tests/tests/protoc_plugin/protos/invocation_testing/split_messages/__init__.py b/src/python/grpcio_tests/tests/protoc_plugin/protos/invocation_testing/split_messages/__init__.py
deleted file mode 100644
index 5772620b602..00000000000
--- a/src/python/grpcio_tests/tests/protoc_plugin/protos/invocation_testing/split_messages/__init__.py
+++ /dev/null
@@ -1,13 +0,0 @@
-# Copyright 2016 gRPC authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
diff --git a/src/python/grpcio_tests/tests/protoc_plugin/protos/invocation_testing/split_messages/messages.proto b/src/python/grpcio_tests/tests/protoc_plugin/protos/invocation_testing/split_messages/sub/messages.proto
similarity index 100%
rename from src/python/grpcio_tests/tests/protoc_plugin/protos/invocation_testing/split_messages/messages.proto
rename to src/python/grpcio_tests/tests/protoc_plugin/protos/invocation_testing/split_messages/sub/messages.proto
diff --git a/src/python/grpcio_tests/tests/protoc_plugin/protos/invocation_testing/split_services/__init__.py b/src/python/grpcio_tests/tests/protoc_plugin/protos/invocation_testing/split_services/__init__.py
deleted file mode 100644
index 5772620b602..00000000000
--- a/src/python/grpcio_tests/tests/protoc_plugin/protos/invocation_testing/split_services/__init__.py
+++ /dev/null
@@ -1,13 +0,0 @@
-# Copyright 2016 gRPC authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
diff --git a/src/python/grpcio_tests/tests/tests.json b/src/python/grpcio_tests/tests/tests.json
index d61297b9187..bbd682b3353 100644
--- a/src/python/grpcio_tests/tests/tests.json
+++ b/src/python/grpcio_tests/tests/tests.json
@@ -3,10 +3,14 @@
   "interop._insecure_intraop_test.InsecureIntraopTest",
   "interop._secure_intraop_test.SecureIntraopTest",
   "protoc_plugin._python_plugin_test.PythonPluginTest",
-  "protoc_plugin._split_definitions_test.SameCommonTest",
-  "protoc_plugin._split_definitions_test.SameSeparateTest",
-  "protoc_plugin._split_definitions_test.SplitCommonTest",
-  "protoc_plugin._split_definitions_test.SplitSeparateTest",
+  "protoc_plugin._split_definitions_test.SameProtoGrpcBeforeProtoProtocStyleTest",
+  "protoc_plugin._split_definitions_test.SameProtoMid2016ProtocStyleTest",
+  "protoc_plugin._split_definitions_test.SameProtoProtoBeforeGrpcProtocStyleTest",
+  "protoc_plugin._split_definitions_test.SameProtoSingleProtocExecutionProtocStyleTest",
+  "protoc_plugin._split_definitions_test.SplitProtoGrpcBeforeProtoProtocStyleTest",
+  "protoc_plugin._split_definitions_test.SplitProtoMid2016ProtocStyleTest",
+  "protoc_plugin._split_definitions_test.SplitProtoProtoBeforeGrpcProtocStyleTest",
+  "protoc_plugin._split_definitions_test.SplitProtoSingleProtocExecutionProtocStyleTest",
   "protoc_plugin.beta_python_plugin_test.PythonPluginTest",
   "reflection._reflection_servicer_test.ReflectionServicerTest",
   "testing._client_test.ClientTest",

From 86eb4ec0ef68482faa960801899be964e545a8b2 Mon Sep 17 00:00:00 2001
From: Nathaniel Manista <nathaniel@google.com>
Date: Mon, 18 Sep 2017 14:22:16 +0000
Subject: [PATCH 20/20] Fix a six.with_metaclass usage mistake

I made this mistake in 2010985ab269c8df0443e4f3782cbdffb083e9d4 but
only with yesterday's release of six 1.11.0 has it started failing
("TypeError: metaclass conflict: the metaclassof a derived class must
be a (non-strict) subclass of the metaclasses of all its bases").
---
 src/python/grpcio_testing/grpc_testing/__init__.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/python/grpcio_testing/grpc_testing/__init__.py b/src/python/grpcio_testing/grpc_testing/__init__.py
index 917e11808e0..994274500c7 100644
--- a/src/python/grpcio_testing/grpc_testing/__init__.py
+++ b/src/python/grpcio_testing/grpc_testing/__init__.py
@@ -213,7 +213,7 @@ class StreamStreamChannelRpc(six.with_metaclass(abc.ABCMeta)):
         raise NotImplementedError()
 
 
-class Channel(six.with_metaclass(abc.ABCMeta), grpc.Channel):
+class Channel(six.with_metaclass(abc.ABCMeta, grpc.Channel)):
     """A grpc.Channel double with which to test a system that invokes RPCs."""
 
     @abc.abstractmethod