From 1128d462c395d064a620c9e62cf29f152cbce33a Mon Sep 17 00:00:00 2001
From: Craig Tiller <ctiller@google.com>
Date: Fri, 3 Mar 2017 16:46:54 -0800
Subject: [PATCH 1/9] Pollset benchmark

---
 CMakeLists.txt                                | 40 +++++++++++
 Makefile                                      | 48 +++++++++++++
 build.yaml                                    | 18 +++++
 test/cpp/microbenchmarks/bm_metadata.cc       |  2 +-
 test/cpp/microbenchmarks/bm_pollset.cc        | 70 +++++++++++++++++++
 .../generated/sources_and_headers.json        | 19 +++++
 tools/run_tests/generated/tests.json          | 22 ++++++
 7 files changed, 218 insertions(+), 1 deletion(-)
 create mode 100644 test/cpp/microbenchmarks/bm_pollset.cc

diff --git a/CMakeLists.txt b/CMakeLists.txt
index dbc2b4b8bf6..784e15da6be 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -600,6 +600,9 @@ endif()
 if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
 add_dependencies(buildtests_cxx bm_metadata)
 endif()
+if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
+add_dependencies(buildtests_cxx bm_pollset)
+endif()
 add_dependencies(buildtests_cxx channel_arguments_test)
 add_dependencies(buildtests_cxx channel_filter_test)
 add_dependencies(buildtests_cxx cli_call_test)
@@ -7916,6 +7919,43 @@ target_link_libraries(bm_metadata
   ${_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(bm_pollset
+  test/cpp/microbenchmarks/bm_pollset.cc
+  third_party/googletest/src/gtest-all.cc
+)
+
+
+target_include_directories(bm_pollset
+  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 ${CMAKE_CURRENT_BINARY_DIR}/third_party/gflags/include
+  PRIVATE third_party/googletest/include
+  PRIVATE third_party/googletest
+  PRIVATE ${_gRPC_PROTO_GENS_DIR}
+)
+
+target_link_libraries(bm_pollset
+  ${_gRPC_PROTOBUF_LIBRARIES}
+  ${_gRPC_ALLTARGETS_LIBRARIES}
+  grpc_benchmark
+  benchmark
+  grpc_test_util
+  grpc
+  gpr_test_util
+  gpr
+  ${_gRPC_GFLAGS_LIBRARIES}
+)
+
 endif()
 endif (gRPC_BUILD_TESTS)
 if (gRPC_BUILD_TESTS)
diff --git a/Makefile b/Makefile
index c2d06feedd3..727bd64c6e1 100644
--- a/Makefile
+++ b/Makefile
@@ -1054,6 +1054,7 @@ bm_fullstack_streaming_pump: $(BINDIR)/$(CONFIG)/bm_fullstack_streaming_pump
 bm_fullstack_trickle: $(BINDIR)/$(CONFIG)/bm_fullstack_trickle
 bm_fullstack_unary_ping_pong: $(BINDIR)/$(CONFIG)/bm_fullstack_unary_ping_pong
 bm_metadata: $(BINDIR)/$(CONFIG)/bm_metadata
+bm_pollset: $(BINDIR)/$(CONFIG)/bm_pollset
 channel_arguments_test: $(BINDIR)/$(CONFIG)/channel_arguments_test
 channel_filter_test: $(BINDIR)/$(CONFIG)/channel_filter_test
 cli_call_test: $(BINDIR)/$(CONFIG)/cli_call_test
@@ -1471,6 +1472,7 @@ buildtests_cxx: privatelibs_cxx \
   $(BINDIR)/$(CONFIG)/bm_fullstack_trickle \
   $(BINDIR)/$(CONFIG)/bm_fullstack_unary_ping_pong \
   $(BINDIR)/$(CONFIG)/bm_metadata \
+  $(BINDIR)/$(CONFIG)/bm_pollset \
   $(BINDIR)/$(CONFIG)/channel_arguments_test \
   $(BINDIR)/$(CONFIG)/channel_filter_test \
   $(BINDIR)/$(CONFIG)/cli_call_test \
@@ -1585,6 +1587,7 @@ buildtests_cxx: privatelibs_cxx \
   $(BINDIR)/$(CONFIG)/bm_fullstack_trickle \
   $(BINDIR)/$(CONFIG)/bm_fullstack_unary_ping_pong \
   $(BINDIR)/$(CONFIG)/bm_metadata \
+  $(BINDIR)/$(CONFIG)/bm_pollset \
   $(BINDIR)/$(CONFIG)/channel_arguments_test \
   $(BINDIR)/$(CONFIG)/channel_filter_test \
   $(BINDIR)/$(CONFIG)/cli_call_test \
@@ -1928,6 +1931,8 @@ test_cxx: buildtests_cxx
 	$(Q) $(BINDIR)/$(CONFIG)/bm_fullstack_unary_ping_pong || ( echo test bm_fullstack_unary_ping_pong failed ; exit 1 )
 	$(E) "[RUN]     Testing bm_metadata"
 	$(Q) $(BINDIR)/$(CONFIG)/bm_metadata || ( echo test bm_metadata failed ; exit 1 )
+	$(E) "[RUN]     Testing bm_pollset"
+	$(Q) $(BINDIR)/$(CONFIG)/bm_pollset || ( echo test bm_pollset failed ; exit 1 )
 	$(E) "[RUN]     Testing channel_arguments_test"
 	$(Q) $(BINDIR)/$(CONFIG)/channel_arguments_test || ( echo test channel_arguments_test failed ; exit 1 )
 	$(E) "[RUN]     Testing channel_filter_test"
@@ -12949,6 +12954,49 @@ endif
 endif
 
 
+BM_POLLSET_SRC = \
+    test/cpp/microbenchmarks/bm_pollset.cc \
+
+BM_POLLSET_OBJS = $(addprefix $(OBJDIR)/$(CONFIG)/, $(addsuffix .o, $(basename $(BM_POLLSET_SRC))))
+ifeq ($(NO_SECURE),true)
+
+# You can't build secure targets if you don't have OpenSSL.
+
+$(BINDIR)/$(CONFIG)/bm_pollset: 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)/$(CONFIG)/bm_pollset: protobuf_dep_error
+
+else
+
+$(BINDIR)/$(CONFIG)/bm_pollset: $(PROTOBUF_DEP) $(BM_POLLSET_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc_benchmark.a $(LIBDIR)/$(CONFIG)/libbenchmark.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a
+	$(E) "[LD]      Linking $@"
+	$(Q) mkdir -p `dirname $@`
+	$(Q) $(LDXX) $(LDFLAGS) $(BM_POLLSET_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc_benchmark.a $(LIBDIR)/$(CONFIG)/libbenchmark.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LDLIBSXX) $(LDLIBS_PROTOBUF) $(LDLIBS) $(LDLIBS_SECURE) $(GTEST_LIB) -o $(BINDIR)/$(CONFIG)/bm_pollset
+
+endif
+
+endif
+
+$(OBJDIR)/$(CONFIG)/test/cpp/microbenchmarks/bm_pollset.o:  $(LIBDIR)/$(CONFIG)/libgrpc_benchmark.a $(LIBDIR)/$(CONFIG)/libbenchmark.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a
+
+deps_bm_pollset: $(BM_POLLSET_OBJS:.o=.dep)
+
+ifneq ($(NO_SECURE),true)
+ifneq ($(NO_DEPS),true)
+-include $(BM_POLLSET_OBJS:.o=.dep)
+endif
+endif
+
+
 CHANNEL_ARGUMENTS_TEST_SRC = \
     test/cpp/common/channel_arguments_test.cc \
 
diff --git a/build.yaml b/build.yaml
index a39ee9f44b6..dae06e6f93e 100644
--- a/build.yaml
+++ b/build.yaml
@@ -3230,6 +3230,24 @@ targets:
   - mac
   - linux
   - posix
+- name: bm_pollset
+  build: test
+  language: c++
+  src:
+  - test/cpp/microbenchmarks/bm_pollset.cc
+  deps:
+  - grpc_benchmark
+  - benchmark
+  - grpc_test_util
+  - grpc
+  - gpr_test_util
+  - gpr
+  args:
+  - --benchmark_min_time=0
+  platforms:
+  - mac
+  - linux
+  - posix
 - name: channel_arguments_test
   gtest: true
   build: test
diff --git a/test/cpp/microbenchmarks/bm_metadata.cc b/test/cpp/microbenchmarks/bm_metadata.cc
index 07c55f42e90..b01a376eb46 100644
--- a/test/cpp/microbenchmarks/bm_metadata.cc
+++ b/test/cpp/microbenchmarks/bm_metadata.cc
@@ -1,6 +1,6 @@
 /*
  *
- * Copyright 2015, Google Inc.
+ * Copyright 2017, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
diff --git a/test/cpp/microbenchmarks/bm_pollset.cc b/test/cpp/microbenchmarks/bm_pollset.cc
new file mode 100644
index 00000000000..adb49f0b79d
--- /dev/null
+++ b/test/cpp/microbenchmarks/bm_pollset.cc
@@ -0,0 +1,70 @@
+/*
+ *
+ * Copyright 2017, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+/* Test out pollset latencies */
+
+#include <grpc/grpc.h>
+
+extern "C" {
+#include "src/core/lib/iomgr/pollset.h"
+}
+
+#include "test/cpp/microbenchmarks/helpers.h"
+#include "third_party/benchmark/include/benchmark/benchmark.h"
+
+static void shutdown_ps_closure(grpc_exec_ctx* exec_ctx, void* ps,
+                                grpc_error* error) {
+  grpc_pollset_destroy(ps);
+}
+
+static void BM_CreateDestroyPollset(benchmark::State& state) {
+  TrackCounters track_counters;
+  size_t ps_sz = grpc_pollset_size();
+  grpc_pollset* ps = gpr_malloc(ps_sz);
+  gpr_mu* mu;
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_closure shutdown_ps_closure;
+  grpc_closure_init(&shutdown_ps_closure, shutdown_ps, ps,
+                    grpc_schedule_on_exec_ctx);
+  while (state.KeepRunning()) {
+    memset(ps, 0, ps_sz);
+    grpc_pollset_init(ps, &mu);
+    grpc_pollset_shutdown(&exec_ctx, ps, shutdown_ps_closure);
+    grpc_exec_ctx_flush(&exec_ctx);
+  }
+  grpc_exec_ctx_finish(&exec_ctx);
+  track_counters.Finish(&state);
+}
+BENCHMARK(BM_CreateDestroyPollset);
+
+BENCHMARK_MAIN();
diff --git a/tools/run_tests/generated/sources_and_headers.json b/tools/run_tests/generated/sources_and_headers.json
index 06fc3799e3f..f8b06bb1725 100644
--- a/tools/run_tests/generated/sources_and_headers.json
+++ b/tools/run_tests/generated/sources_and_headers.json
@@ -2586,6 +2586,25 @@
     "third_party": false, 
     "type": "target"
   }, 
+  {
+    "deps": [
+      "benchmark", 
+      "gpr", 
+      "gpr_test_util", 
+      "grpc", 
+      "grpc_benchmark", 
+      "grpc_test_util"
+    ], 
+    "headers": [], 
+    "is_filegroup": false, 
+    "language": "c++", 
+    "name": "bm_pollset", 
+    "src": [
+      "test/cpp/microbenchmarks/bm_pollset.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 f24694e3c99..4b01be8494d 100644
--- a/tools/run_tests/generated/tests.json
+++ b/tools/run_tests/generated/tests.json
@@ -2779,6 +2779,28 @@
       "posix"
     ]
   }, 
+  {
+    "args": [
+      "--benchmark_min_time=0"
+    ], 
+    "ci_platforms": [
+      "linux", 
+      "mac", 
+      "posix"
+    ], 
+    "cpu_cost": 1.0, 
+    "exclude_configs": [], 
+    "exclude_iomgrs": [], 
+    "flaky": false, 
+    "gtest": false, 
+    "language": "c++", 
+    "name": "bm_pollset", 
+    "platforms": [
+      "linux", 
+      "mac", 
+      "posix"
+    ]
+  }, 
   {
     "args": [], 
     "ci_platforms": [

From ab314ee9a6dd633c9e5d5e8bf2e91cb14c4f40a7 Mon Sep 17 00:00:00 2001
From: Craig Tiller <ctiller@google.com>
Date: Fri, 3 Mar 2017 17:18:20 -0800
Subject: [PATCH 2/9] Add some pollset benchmarks

---
 test/cpp/microbenchmarks/bm_pollset.cc | 104 +++++++++++++++++++++++--
 1 file changed, 98 insertions(+), 6 deletions(-)

diff --git a/test/cpp/microbenchmarks/bm_pollset.cc b/test/cpp/microbenchmarks/bm_pollset.cc
index adb49f0b79d..f7c3b7951d2 100644
--- a/test/cpp/microbenchmarks/bm_pollset.cc
+++ b/test/cpp/microbenchmarks/bm_pollset.cc
@@ -34,23 +34,27 @@
 /* Test out pollset latencies */
 
 #include <grpc/grpc.h>
+#include <grpc/support/alloc.h>
 
 extern "C" {
+#include "src/core/lib/iomgr/ev_posix.h"
 #include "src/core/lib/iomgr/pollset.h"
+#include "src/core/lib/iomgr/wakeup_fd_posix.h"
 }
 
 #include "test/cpp/microbenchmarks/helpers.h"
 #include "third_party/benchmark/include/benchmark/benchmark.h"
 
-static void shutdown_ps_closure(grpc_exec_ctx* exec_ctx, void* ps,
-                                grpc_error* error) {
-  grpc_pollset_destroy(ps);
+auto& force_library_initialization = Library::get();
+
+static void shutdown_ps(grpc_exec_ctx* exec_ctx, void* ps, grpc_error* error) {
+  grpc_pollset_destroy(static_cast<grpc_pollset*>(ps));
 }
 
 static void BM_CreateDestroyPollset(benchmark::State& state) {
   TrackCounters track_counters;
   size_t ps_sz = grpc_pollset_size();
-  grpc_pollset* ps = gpr_malloc(ps_sz);
+  grpc_pollset* ps = static_cast<grpc_pollset*>(gpr_malloc(ps_sz));
   gpr_mu* mu;
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   grpc_closure shutdown_ps_closure;
@@ -59,12 +63,100 @@ static void BM_CreateDestroyPollset(benchmark::State& state) {
   while (state.KeepRunning()) {
     memset(ps, 0, ps_sz);
     grpc_pollset_init(ps, &mu);
-    grpc_pollset_shutdown(&exec_ctx, ps, shutdown_ps_closure);
+    gpr_mu_lock(mu);
+    grpc_pollset_shutdown(&exec_ctx, ps, &shutdown_ps_closure);
+    gpr_mu_unlock(mu);
     grpc_exec_ctx_flush(&exec_ctx);
   }
   grpc_exec_ctx_finish(&exec_ctx);
-  track_counters.Finish(&state);
+  gpr_free(ps);
+  track_counters.Finish(state);
 }
 BENCHMARK(BM_CreateDestroyPollset);
 
+static void BM_PollEmptyPollset(benchmark::State& state) {
+  TrackCounters track_counters;
+  size_t ps_sz = grpc_pollset_size();
+  grpc_pollset* ps = static_cast<grpc_pollset*>(gpr_zalloc(ps_sz));
+  gpr_mu* mu;
+  grpc_pollset_init(ps, &mu);
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  gpr_timespec now = gpr_time_0(GPR_CLOCK_MONOTONIC);
+  gpr_timespec deadline = gpr_inf_past(GPR_CLOCK_MONOTONIC);
+  gpr_mu_lock(mu);
+  while (state.KeepRunning()) {
+    grpc_pollset_worker* worker;
+    GRPC_ERROR_UNREF(grpc_pollset_work(&exec_ctx, ps, &worker, now, deadline));
+  }
+  grpc_closure shutdown_ps_closure;
+  grpc_closure_init(&shutdown_ps_closure, shutdown_ps, ps,
+                    grpc_schedule_on_exec_ctx);
+  grpc_pollset_shutdown(&exec_ctx, ps, &shutdown_ps_closure);
+  gpr_mu_unlock(mu);
+  grpc_exec_ctx_finish(&exec_ctx);
+  gpr_free(ps);
+  track_counters.Finish(state);
+}
+BENCHMARK(BM_PollEmptyPollset);
+
+template <class F>
+grpc_closure* MakeClosure(F f, grpc_closure_scheduler* scheduler) {
+  struct C : public grpc_closure {
+    C(F f, grpc_closure_scheduler* scheduler) : f_(f) {
+      grpc_closure_init(this, C::cbfn, this, scheduler);
+    }
+    static void cbfn(grpc_exec_ctx* exec_ctx, void* arg, grpc_error* error) {
+      static_cast<C*>(arg)->f_();
+    }
+    F f_;
+  };
+  return new C(f, scheduler);
+}
+
+static void BM_PollAfterWakeup(benchmark::State& state) {
+  TrackCounters track_counters;
+  size_t ps_sz = grpc_pollset_size();
+  grpc_pollset* ps = static_cast<grpc_pollset*>(gpr_zalloc(ps_sz));
+  gpr_mu* mu;
+  grpc_pollset_init(ps, &mu);
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  gpr_timespec now = gpr_time_0(GPR_CLOCK_MONOTONIC);
+  gpr_timespec deadline = gpr_inf_future(GPR_CLOCK_MONOTONIC);
+  grpc_wakeup_fd wakeup_fd;
+  GRPC_ERROR_UNREF(grpc_wakeup_fd_init(&wakeup_fd));
+  grpc_fd* wakeup = grpc_fd_create(wakeup_fd.read_fd, "wakeup_read");
+  grpc_pollset_add_fd(&exec_ctx, ps, wakeup);
+  bool done = false;
+  grpc_closure* continue_closure = MakeClosure(
+      [&]() {
+        GRPC_ERROR_UNREF(grpc_wakeup_fd_consume_wakeup(&wakeup_fd));
+        if (!state.KeepRunning()) {
+          done = true;
+          return;
+        }
+        GRPC_ERROR_UNREF(grpc_wakeup_fd_wakeup(&wakeup_fd));
+        grpc_fd_notify_on_read(&exec_ctx, wakeup, continue_closure);
+      },
+      grpc_schedule_on_exec_ctx);
+  GRPC_ERROR_UNREF(grpc_wakeup_fd_wakeup(&wakeup_fd));
+  grpc_fd_notify_on_read(&exec_ctx, wakeup, continue_closure);
+  gpr_mu_lock(mu);
+  while (!done) {
+    grpc_pollset_worker* worker;
+    GRPC_ERROR_UNREF(grpc_pollset_work(&exec_ctx, ps, &worker, now, deadline));
+  }
+  grpc_fd_orphan(&exec_ctx, wakeup, NULL, NULL, "done");
+  wakeup_fd.read_fd = 0;
+  grpc_closure shutdown_ps_closure;
+  grpc_closure_init(&shutdown_ps_closure, shutdown_ps, ps,
+                    grpc_schedule_on_exec_ctx);
+  grpc_pollset_shutdown(&exec_ctx, ps, &shutdown_ps_closure);
+  gpr_mu_unlock(mu);
+  grpc_exec_ctx_finish(&exec_ctx);
+  grpc_wakeup_fd_destroy(&wakeup_fd);
+  gpr_free(ps);
+  track_counters.Finish(state);
+}
+BENCHMARK(BM_PollAfterWakeup);
+
 BENCHMARK_MAIN();

From 055abd65fb3db3f679faf378c09d9f0a6af82d07 Mon Sep 17 00:00:00 2001
From: Craig Tiller <ctiller@google.com>
Date: Fri, 3 Mar 2017 17:20:36 -0800
Subject: [PATCH 3/9] Fix linux

---
 test/cpp/microbenchmarks/bm_pollset.cc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/test/cpp/microbenchmarks/bm_pollset.cc b/test/cpp/microbenchmarks/bm_pollset.cc
index f7c3b7951d2..9d7fac39c77 100644
--- a/test/cpp/microbenchmarks/bm_pollset.cc
+++ b/test/cpp/microbenchmarks/bm_pollset.cc
@@ -45,6 +45,8 @@ extern "C" {
 #include "test/cpp/microbenchmarks/helpers.h"
 #include "third_party/benchmark/include/benchmark/benchmark.h"
 
+#include <string.h>
+
 auto& force_library_initialization = Library::get();
 
 static void shutdown_ps(grpc_exec_ctx* exec_ctx, void* ps, grpc_error* error) {

From 77108238509e2c8c236541a0ef8cb7a9d7a34e0d Mon Sep 17 00:00:00 2001
From: Craig Tiller <ctiller@google.com>
Date: Thu, 9 Mar 2017 10:04:50 -0800
Subject: [PATCH 4/9] Add speed of light measures

---
 test/cpp/microbenchmarks/bm_pollset.cc | 87 +++++++++++++++++++++++++-
 1 file changed, 85 insertions(+), 2 deletions(-)

diff --git a/test/cpp/microbenchmarks/bm_pollset.cc b/test/cpp/microbenchmarks/bm_pollset.cc
index 9d7fac39c77..da06eae5078 100644
--- a/test/cpp/microbenchmarks/bm_pollset.cc
+++ b/test/cpp/microbenchmarks/bm_pollset.cc
@@ -35,10 +35,13 @@
 
 #include <grpc/grpc.h>
 #include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/useful.h>
 
 extern "C" {
 #include "src/core/lib/iomgr/ev_posix.h"
 #include "src/core/lib/iomgr/pollset.h"
+#include "src/core/lib/iomgr/port.h"
 #include "src/core/lib/iomgr/wakeup_fd_posix.h"
 }
 
@@ -47,6 +50,12 @@ extern "C" {
 
 #include <string.h>
 
+#ifdef GRPC_LINUX_MULTIPOLL_WITH_EPOLL
+#include <sys/epoll.h>
+#include <sys/eventfd.h>
+#include <unistd.h>
+#endif
+
 auto& force_library_initialization = Library::get();
 
 static void shutdown_ps(grpc_exec_ctx* exec_ctx, void* ps, grpc_error* error) {
@@ -76,6 +85,46 @@ static void BM_CreateDestroyPollset(benchmark::State& state) {
 }
 BENCHMARK(BM_CreateDestroyPollset);
 
+#ifdef GRPC_LINUX_MULTIPOLL_WITH_EPOLL
+static void BM_PollEmptyPollset_SpeedOfLight(benchmark::State& state) {
+  // equivalent to BM_PollEmptyPollset, but just use the OS primitives to guage
+  // what the speed of light would be if we abstracted perfectly
+  TrackCounters track_counters;
+  int epfd = epoll_create1(0);
+  GPR_ASSERT(epfd != -1);
+  size_t nev = state.range(0);
+  size_t nfd = state.range(1);
+  epoll_event* ev = new epoll_event[nev];
+  std::vector<int> fds;
+  for (size_t i = 0; i < nfd; i++) {
+    fds.push_back(eventfd(0, 0));
+    epoll_event ev;
+    ev.events = EPOLLIN;
+    epoll_ctl(epfd, EPOLL_CTL_ADD, fds.back(), &ev);
+  }
+  while (state.KeepRunning()) {
+    epoll_wait(epfd, ev, nev, 0);
+  }
+  for (auto fd : fds) {
+    close(fd);
+  }
+  close(epfd);
+  delete[] ev;
+  track_counters.Finish(state);
+}
+BENCHMARK(BM_PollEmptyPollset_SpeedOfLight)
+    ->Args({1, 0})
+    ->Args({1, 1})
+    ->Args({1, 10})
+    ->Args({1, 100})
+    ->Args({1, 1000})
+    ->Args({1, 10000})
+    ->Args({1, 100000})
+    ->Args({10, 1})
+    ->Args({100, 1})
+    ->Args({1000, 1});
+#endif
+
 static void BM_PollEmptyPollset(benchmark::State& state) {
   TrackCounters track_counters;
   size_t ps_sz = grpc_pollset_size();
@@ -115,7 +164,41 @@ grpc_closure* MakeClosure(F f, grpc_closure_scheduler* scheduler) {
   return new C(f, scheduler);
 }
 
-static void BM_PollAfterWakeup(benchmark::State& state) {
+#ifdef GRPC_LINUX_MULTIPOLL_WITH_EPOLL
+static void BM_SingleThreadPollOneFd_SpeedOfLight(benchmark::State& state) {
+  // equivalent to BM_PollEmptyPollset, but just use the OS primitives to guage
+  // what the speed of light would be if we abstracted perfectly
+  TrackCounters track_counters;
+  int epfd = epoll_create1(0);
+  GPR_ASSERT(epfd != -1);
+  epoll_event ev[100];
+  int fd = eventfd(0, EFD_NONBLOCK);
+  ev[0].events = EPOLLIN;
+  epoll_ctl(epfd, EPOLL_CTL_ADD, fd, &ev[0]);
+  while (state.KeepRunning()) {
+    int err;
+    do {
+      err = eventfd_write(fd, 1);
+    } while (err < 0 && errno == EINTR);
+    GPR_ASSERT(err == 0);
+    do {
+      err = epoll_wait(epfd, ev, GPR_ARRAY_SIZE(ev), 0);
+    } while (err < 0 && errno == EINTR);
+    GPR_ASSERT(err == 1);
+    eventfd_t value;
+    do {
+      err = eventfd_read(fd, &value);
+    } while (err < 0 && errno == EINTR);
+    GPR_ASSERT(err == 0);
+  }
+  close(fd);
+  close(epfd);
+  track_counters.Finish(state);
+}
+BENCHMARK(BM_SingleThreadPollOneFd_SpeedOfLight);
+#endif
+
+static void BM_SingleThreadPollOneFd(benchmark::State& state) {
   TrackCounters track_counters;
   size_t ps_sz = grpc_pollset_size();
   grpc_pollset* ps = static_cast<grpc_pollset*>(gpr_zalloc(ps_sz));
@@ -159,6 +242,6 @@ static void BM_PollAfterWakeup(benchmark::State& state) {
   gpr_free(ps);
   track_counters.Finish(state);
 }
-BENCHMARK(BM_PollAfterWakeup);
+BENCHMARK(BM_SingleThreadPollOneFd);
 
 BENCHMARK_MAIN();

From 2b182c2b4b82f3443111f79227de6a492fa22c78 Mon Sep 17 00:00:00 2001
From: Craig Tiller <ctiller@google.com>
Date: Thu, 9 Mar 2017 16:19:58 -0800
Subject: [PATCH 5/9] Make ASAN happy

---
 test/cpp/microbenchmarks/bm_pollset.cc | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/test/cpp/microbenchmarks/bm_pollset.cc b/test/cpp/microbenchmarks/bm_pollset.cc
index da06eae5078..0f3d3cef66a 100644
--- a/test/cpp/microbenchmarks/bm_pollset.cc
+++ b/test/cpp/microbenchmarks/bm_pollset.cc
@@ -150,14 +150,20 @@ static void BM_PollEmptyPollset(benchmark::State& state) {
 }
 BENCHMARK(BM_PollEmptyPollset);
 
+class Closure : public grpc_closure {
+ public:
+  virtual ~Closure() {}
+};
+
 template <class F>
-grpc_closure* MakeClosure(F f, grpc_closure_scheduler* scheduler) {
-  struct C : public grpc_closure {
+Closure* MakeClosure(F f, grpc_closure_scheduler* scheduler) {
+  struct C : public Closure {
     C(F f, grpc_closure_scheduler* scheduler) : f_(f) {
       grpc_closure_init(this, C::cbfn, this, scheduler);
     }
     static void cbfn(grpc_exec_ctx* exec_ctx, void* arg, grpc_error* error) {
-      static_cast<C*>(arg)->f_();
+      C* p = static_cast<C*>(arg);
+      p->f_();
     }
     F f_;
   };
@@ -212,7 +218,7 @@ static void BM_SingleThreadPollOneFd(benchmark::State& state) {
   grpc_fd* wakeup = grpc_fd_create(wakeup_fd.read_fd, "wakeup_read");
   grpc_pollset_add_fd(&exec_ctx, ps, wakeup);
   bool done = false;
-  grpc_closure* continue_closure = MakeClosure(
+  Closure* continue_closure = MakeClosure(
       [&]() {
         GRPC_ERROR_UNREF(grpc_wakeup_fd_consume_wakeup(&wakeup_fd));
         if (!state.KeepRunning()) {
@@ -241,6 +247,7 @@ static void BM_SingleThreadPollOneFd(benchmark::State& state) {
   grpc_wakeup_fd_destroy(&wakeup_fd);
   gpr_free(ps);
   track_counters.Finish(state);
+  delete continue_closure;
 }
 BENCHMARK(BM_SingleThreadPollOneFd);
 

From 3a35189f9b47696149f48505d0a8f18dfd7f9f89 Mon Sep 17 00:00:00 2001
From: Craig Tiller <ctiller@google.com>
Date: Fri, 10 Mar 2017 07:39:26 -0800
Subject: [PATCH 6/9] Fix build

---
 CMakeLists.txt                                     | 2 ++
 Makefile                                           | 6 +++---
 build.yaml                                         | 2 ++
 tools/run_tests/generated/sources_and_headers.json | 2 ++
 4 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 933426d73ca..df1565676b5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -8044,7 +8044,9 @@ target_link_libraries(bm_pollset
   ${_gRPC_ALLTARGETS_LIBRARIES}
   grpc_benchmark
   benchmark
+  grpc++_test_util
   grpc_test_util
+  grpc++
   grpc
   gpr_test_util
   gpr
diff --git a/Makefile b/Makefile
index 33c330d02ed..63c76a023c4 100644
--- a/Makefile
+++ b/Makefile
@@ -13097,16 +13097,16 @@ $(BINDIR)/$(CONFIG)/bm_pollset: protobuf_dep_error
 
 else
 
-$(BINDIR)/$(CONFIG)/bm_pollset: $(PROTOBUF_DEP) $(BM_POLLSET_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc_benchmark.a $(LIBDIR)/$(CONFIG)/libbenchmark.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a
+$(BINDIR)/$(CONFIG)/bm_pollset: $(PROTOBUF_DEP) $(BM_POLLSET_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc_benchmark.a $(LIBDIR)/$(CONFIG)/libbenchmark.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a
 	$(E) "[LD]      Linking $@"
 	$(Q) mkdir -p `dirname $@`
-	$(Q) $(LDXX) $(LDFLAGS) $(BM_POLLSET_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc_benchmark.a $(LIBDIR)/$(CONFIG)/libbenchmark.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LDLIBSXX) $(LDLIBS_PROTOBUF) $(LDLIBS) $(LDLIBS_SECURE) $(GTEST_LIB) -o $(BINDIR)/$(CONFIG)/bm_pollset
+	$(Q) $(LDXX) $(LDFLAGS) $(BM_POLLSET_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc_benchmark.a $(LIBDIR)/$(CONFIG)/libbenchmark.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LDLIBSXX) $(LDLIBS_PROTOBUF) $(LDLIBS) $(LDLIBS_SECURE) $(GTEST_LIB) -o $(BINDIR)/$(CONFIG)/bm_pollset
 
 endif
 
 endif
 
-$(OBJDIR)/$(CONFIG)/test/cpp/microbenchmarks/bm_pollset.o:  $(LIBDIR)/$(CONFIG)/libgrpc_benchmark.a $(LIBDIR)/$(CONFIG)/libbenchmark.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a
+$(OBJDIR)/$(CONFIG)/test/cpp/microbenchmarks/bm_pollset.o:  $(LIBDIR)/$(CONFIG)/libgrpc_benchmark.a $(LIBDIR)/$(CONFIG)/libbenchmark.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a
 
 deps_bm_pollset: $(BM_POLLSET_OBJS:.o=.dep)
 
diff --git a/build.yaml b/build.yaml
index 5a8f57a2c71..5294929431f 100644
--- a/build.yaml
+++ b/build.yaml
@@ -3276,7 +3276,9 @@ targets:
   deps:
   - grpc_benchmark
   - benchmark
+  - grpc++_test_util
   - grpc_test_util
+  - grpc++
   - grpc
   - gpr_test_util
   - gpr
diff --git a/tools/run_tests/generated/sources_and_headers.json b/tools/run_tests/generated/sources_and_headers.json
index 58d929806fd..c0cd6c04964 100644
--- a/tools/run_tests/generated/sources_and_headers.json
+++ b/tools/run_tests/generated/sources_and_headers.json
@@ -2645,6 +2645,8 @@
       "gpr", 
       "gpr_test_util", 
       "grpc", 
+      "grpc++", 
+      "grpc++_test_util", 
       "grpc_benchmark", 
       "grpc_test_util"
     ], 

From 6a4c1a37cc41d4f8114ea8116134d510af5f2dc6 Mon Sep 17 00:00:00 2001
From: Craig Tiller <ctiller@google.com>
Date: Fri, 10 Mar 2017 14:18:00 -0800
Subject: [PATCH 7/9] Add benchmark to list

---
 tools/profiling/microbenchmarks/bm_json.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tools/profiling/microbenchmarks/bm_json.py b/tools/profiling/microbenchmarks/bm_json.py
index c48a63b791f..4695f829f41 100644
--- a/tools/profiling/microbenchmarks/bm_json.py
+++ b/tools/profiling/microbenchmarks/bm_json.py
@@ -98,6 +98,10 @@ _BM_SPECS = {
     'tpl': [],
     'dyn': ['request_size'],
   },
+  'BM_PollEmptyPollset_SpeedOfLight': {
+    'tpl': [],
+    'dyn': ['request_size', 'request_count'],
+  }
 }
 
 def numericalize(s):

From d194f59939de8e9956e0d040266e3da269879a01 Mon Sep 17 00:00:00 2001
From: Siddharth Shukla <siddharth.shukla@uber.com>
Date: Sat, 11 Mar 2017 19:12:43 +0100
Subject: [PATCH 8/9] Make testing scripts python3.x compatible

Update run_tests/*.py to use six based isomorphisms and print function
from __future__ module.
---
 .../run_tests/performance/bq_upload_result.py |  8 ++-
 .../python_utils/filter_pull_request_tests.py |  5 +-
 tools/run_tests/python_utils/report_utils.py  |  3 +-
 tools/run_tests/run_build_statistics.py       |  4 +-
 tools/run_tests/run_interop_tests.py          | 11 ++--
 tools/run_tests/run_performance_tests.py      |  9 +--
 tools/run_tests/run_stress_tests.py           | 14 ++---
 tools/run_tests/run_tests.py                  |  3 +-
 tools/run_tests/run_tests_matrix.py           |  2 +
 .../sanity/check_sources_and_headers.py       |  2 +
 .../run_tests/sanity/check_test_filtering.py  |  2 +-
 tools/run_tests/sanity/check_version.py       | 16 +++--
 .../run_tests/sanity/core_banned_functions.py |  4 +-
 tools/run_tests/start_port_server.py          |  4 +-
 tools/run_tests/stress_test/run_on_gke.py     | 58 ++++++++++---------
 15 files changed, 87 insertions(+), 58 deletions(-)

diff --git a/tools/run_tests/performance/bq_upload_result.py b/tools/run_tests/performance/bq_upload_result.py
index 89d2a9b320f..e2e1393509e 100755
--- a/tools/run_tests/performance/bq_upload_result.py
+++ b/tools/run_tests/performance/bq_upload_result.py
@@ -30,6 +30,8 @@
 
 # Uploads performance benchmark result file to bigquery.
 
+from __future__ import print_function
+
 import argparse
 import calendar
 import json
@@ -70,7 +72,7 @@ def _upload_netperf_latency_csv_to_bigquery(dataset_id, table_id, result_file):
   _create_results_table(bq, dataset_id, table_id)
 
   if not _insert_result(bq, dataset_id, table_id, scenario_result, flatten=False):
-    print 'Error uploading result to bigquery.'
+    print('Error uploading result to bigquery.')
     sys.exit(1)
 
 
@@ -82,7 +84,7 @@ def _upload_scenario_result_to_bigquery(dataset_id, table_id, result_file):
   _create_results_table(bq, dataset_id, table_id)
 
   if not _insert_result(bq, dataset_id, table_id, scenario_result):
-    print 'Error uploading result to bigquery.'
+    print('Error uploading result to bigquery.')
     sys.exit(1)
 
 
@@ -179,4 +181,4 @@ if args.file_format == 'netperf_latency_csv':
   _upload_netperf_latency_csv_to_bigquery(dataset_id, table_id, args.file_to_upload)
 else:
   _upload_scenario_result_to_bigquery(dataset_id, table_id, args.file_to_upload)
-print 'Successfully uploaded %s to BigQuery.\n' % args.file_to_upload
+print('Successfully uploaded %s to BigQuery.\n' % args.file_to_upload)
diff --git a/tools/run_tests/python_utils/filter_pull_request_tests.py b/tools/run_tests/python_utils/filter_pull_request_tests.py
index 3734f025d5f..041e3491627 100644
--- a/tools/run_tests/python_utils/filter_pull_request_tests.py
+++ b/tools/run_tests/python_utils/filter_pull_request_tests.py
@@ -30,7 +30,10 @@
 
 """Filter out tests based on file differences compared to merge target branch"""
 
+from __future__ import print_function
+
 import re
+import six
 from subprocess import check_output
 
 
@@ -125,7 +128,7 @@ _WHITELIST_DICT = {
 }
 
 # Add all triggers to their respective test suites
-for trigger, test_suites in _WHITELIST_DICT.iteritems():
+for trigger, test_suites in six.iteritems(_WHITELIST_DICT):
   for test_suite in test_suites:
     test_suite.add_trigger(trigger)
 
diff --git a/tools/run_tests/python_utils/report_utils.py b/tools/run_tests/python_utils/report_utils.py
index 9dad60408f2..131772f55fc 100644
--- a/tools/run_tests/python_utils/report_utils.py
+++ b/tools/run_tests/python_utils/report_utils.py
@@ -40,6 +40,7 @@ except (ImportError):
 import os
 import string
 import xml.etree.cElementTree as ET
+import six
 
 
 def _filter_msg(msg, output_format):
@@ -63,7 +64,7 @@ def render_junit_xml_report(resultset, xml_report, suite_package='grpc',
   root = ET.Element('testsuites')
   testsuite = ET.SubElement(root, 'testsuite', id='1', package=suite_package,
                             name=suite_name)
-  for shortname, results in resultset.iteritems():
+  for shortname, results in six.iteritems(resultset):
     for result in results:
       xml_test = ET.SubElement(testsuite, 'testcase', name=shortname)
       if result.elapsed_time:
diff --git a/tools/run_tests/run_build_statistics.py b/tools/run_tests/run_build_statistics.py
index 654cf95a38c..e33e01e7034 100755
--- a/tools/run_tests/run_build_statistics.py
+++ b/tools/run_tests/run_build_statistics.py
@@ -30,6 +30,8 @@
 
 """Tool to get build statistics from Jenkins and upload to BigQuery."""
 
+from __future__ import print_function
+
 import argparse
 import jenkinsapi
 from jenkinsapi.custom_exceptions import JenkinsAPIException
@@ -243,6 +245,6 @@ for build_name in _BUILDS.keys() if 'all' in args.builds else args.builds:
     rows = [big_query_utils.make_row(build_number, build_result)]
     if not big_query_utils.insert_rows(bq, _PROJECT_ID, _DATASET_ID, build_name, 
                                        rows):
-      print '====> Error uploading result to bigquery.'
+      print('====> Error uploading result to bigquery.')
       sys.exit(1)
 
diff --git a/tools/run_tests/run_interop_tests.py b/tools/run_tests/run_interop_tests.py
index 161fa81956b..ace142ed8ad 100755
--- a/tools/run_tests/run_interop_tests.py
+++ b/tools/run_tests/run_interop_tests.py
@@ -44,6 +44,7 @@ import sys
 import tempfile
 import time
 import uuid
+import six
 
 import python_utils.dockerjob as dockerjob
 import python_utils.jobset as jobset
@@ -885,7 +886,7 @@ if not args.use_docker and servers:
 
 languages = set(_LANGUAGES[l]
                 for l in itertools.chain.from_iterable(
-                    _LANGUAGES.iterkeys() if x == 'all' else [x]
+                    six.iterkeys(_LANGUAGES) if x == 'all' else [x]
                     for x in args.language))
 
 languages_http2_badserver_interop = set()
@@ -925,7 +926,7 @@ if args.use_docker:
     else:
       jobset.message('FAILED', 'Failed to build interop docker images.',
                      do_newline=True)
-      for image in docker_images.itervalues():
+      for image in six.itervalues(docker_images):
         dockerjob.remove_image(image, skip_nonexistent=True)
       sys.exit(1)
 
@@ -1053,7 +1054,7 @@ try:
 
   if not jobs:
     print('No jobs to run.')
-    for image in docker_images.itervalues():
+    for image in six.itervalues(docker_images):
       dockerjob.remove_image(image, skip_nonexistent=True)
     sys.exit(1)
 
@@ -1093,9 +1094,9 @@ finally:
     if not job.is_running():
       print('Server "%s" has exited prematurely.' % server)
 
-  dockerjob.finish_jobs([j for j in server_jobs.itervalues()])
+  dockerjob.finish_jobs([j for j in six.itervalues(server_jobs)])
 
-  for image in docker_images.itervalues():
+  for image in six.itervalues(docker_images):
     if not args.manual_run:
       print('Removing docker image %s' % image)
       dockerjob.remove_image(image)
diff --git a/tools/run_tests/run_performance_tests.py b/tools/run_tests/run_performance_tests.py
index ee4102c5913..c79f47a3175 100755
--- a/tools/run_tests/run_performance_tests.py
+++ b/tools/run_tests/run_performance_tests.py
@@ -46,6 +46,7 @@ import tempfile
 import time
 import traceback
 import uuid
+import six
 
 import performance.scenario_config as scenario_config
 import python_utils.jobset as jobset
@@ -502,8 +503,8 @@ args = argp.parse_args()
 
 languages = set(scenario_config.LANGUAGES[l]
                 for l in itertools.chain.from_iterable(
-                      scenario_config.LANGUAGES.iterkeys() if x == 'all' else [x]
-                      for x in args.language))
+                      six.iterkeys(scenario_config.LANGUAGES) if x == 'all'
+                      else [x] for x in args.language))
 
 
 # Put together set of remote hosts where to run and build
@@ -572,8 +573,8 @@ for scenario in scenarios:
         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)
       total_scenario_failures += scenario_failures
-      merged_resultset = dict(itertools.chain(merged_resultset.iteritems(),
-                                              resultset.iteritems()))
+      merged_resultset = dict(itertools.chain(six.iteritems(merged_resultset),
+                                              six.iteritems(resultset)))
     finally:
       # Consider qps workers that need to be killed as failures
       qps_workers_killed += finish_qps_workers(scenario.workers)
diff --git a/tools/run_tests/run_stress_tests.py b/tools/run_tests/run_stress_tests.py
index a94a615b886..3a2661a9aa6 100755
--- a/tools/run_tests/run_stress_tests.py
+++ b/tools/run_tests/run_stress_tests.py
@@ -43,6 +43,7 @@ import sys
 import tempfile
 import time
 import uuid
+import six
 
 import python_utils.dockerjob as dockerjob
 import python_utils.jobset as jobset
@@ -239,9 +240,8 @@ servers = set(
     for s in itertools.chain.from_iterable(_SERVERS if x == 'all' else [x]
                                            for x in args.server))
 
-languages = set(_LANGUAGES[l]
-                for l in itertools.chain.from_iterable(_LANGUAGES.iterkeys(
-                ) if x == 'all' else [x] for x in args.language))
+languages = set(_LANGUAGES[l] for l in itertools.chain.from_iterable(
+  six.iterkeys(_LANGUAGES) if x == 'all' else [x] for x in args.language))
 
 docker_images = {}
 # languages for which to build docker images
@@ -267,7 +267,7 @@ if build_jobs:
     jobset.message('FAILED',
                    'Failed to build interop docker images.',
                    do_newline=True)
-    for image in docker_images.itervalues():
+    for image in six.itervalues(docker_images):
       dockerjob.remove_image(image, skip_nonexistent=True)
     sys.exit(1)
 
@@ -306,7 +306,7 @@ try:
 
   if not jobs:
     print('No jobs to run.')
-    for image in docker_images.itervalues():
+    for image in six.itervalues(docker_images):
       dockerjob.remove_image(image, skip_nonexistent=True)
     sys.exit(1)
 
@@ -324,8 +324,8 @@ finally:
     if not job.is_running():
       print('Server "%s" has exited prematurely.' % server)
 
-  dockerjob.finish_jobs([j for j in server_jobs.itervalues()])
+  dockerjob.finish_jobs([j for j in six.itervalues(server_jobs)])
 
-  for image in docker_images.itervalues():
+  for image in six.itervalues(docker_images):
     print('Removing docker image %s' % image)
     dockerjob.remove_image(image)
diff --git a/tools/run_tests/run_tests.py b/tools/run_tests/run_tests.py
index 43b8f8184e2..cba91a9a632 100755
--- a/tools/run_tests/run_tests.py
+++ b/tools/run_tests/run_tests.py
@@ -54,6 +54,7 @@ import traceback
 import time
 from six.moves import urllib
 import uuid
+import six
 
 import python_utils.jobset as jobset
 import python_utils.report_utils as report_utils
@@ -771,7 +772,7 @@ class CSharpLanguage(object):
         runtime_cmd = ['mono']
 
     specs = []
-    for assembly in tests_by_assembly.iterkeys():
+    for assembly in six.iterkeys(tests_by_assembly):
       assembly_file = 'src/csharp/%s/%s/%s%s' % (assembly,
                                                  assembly_subdir,
                                                  assembly,
diff --git a/tools/run_tests/run_tests_matrix.py b/tools/run_tests/run_tests_matrix.py
index 47422451f8d..191228e4db7 100755
--- a/tools/run_tests/run_tests_matrix.py
+++ b/tools/run_tests/run_tests_matrix.py
@@ -30,6 +30,8 @@
 
 """Run test matrix."""
 
+from __future__ import print_function
+
 import argparse
 import multiprocessing
 import os
diff --git a/tools/run_tests/sanity/check_sources_and_headers.py b/tools/run_tests/sanity/check_sources_and_headers.py
index a86db02b80b..0bb92fda8b5 100755
--- a/tools/run_tests/sanity/check_sources_and_headers.py
+++ b/tools/run_tests/sanity/check_sources_and_headers.py
@@ -28,6 +28,8 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+from __future__ import print_function
+
 import json
 import os
 import re
diff --git a/tools/run_tests/sanity/check_test_filtering.py b/tools/run_tests/sanity/check_test_filtering.py
index 290a6e2ddf6..aceee6d4d72 100755
--- a/tools/run_tests/sanity/check_test_filtering.py
+++ b/tools/run_tests/sanity/check_test_filtering.py
@@ -62,7 +62,7 @@ class TestFilteringTest(unittest.TestCase):
     def _get_changed_files(foo):
       return changed_files
     filter_pull_request_tests._get_changed_files = _get_changed_files
-    print
+    print()
     filtered_jobs = filter_pull_request_tests.filter_tests(all_jobs, "test")
 
     # Make sure sanity tests aren't being filtered out
diff --git a/tools/run_tests/sanity/check_version.py b/tools/run_tests/sanity/check_version.py
index e62f3908185..d8162fb3c57 100755
--- a/tools/run_tests/sanity/check_version.py
+++ b/tools/run_tests/sanity/check_version.py
@@ -29,6 +29,8 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+from __future__ import print_function
+
 import sys
 import yaml
 import os
@@ -48,13 +50,13 @@ try:
     'git rev-parse --abbrev-ref HEAD',
     shell=True)
 except:
-  print 'WARNING: not a git repository'
+  print('WARNING: not a git repository')
   branch_name = None
 
 if branch_name is not None:
   m = re.match(r'^release-([0-9]+)_([0-9]+)$', branch_name)
   if m:
-    print 'RELEASE branch'
+    print('RELEASE branch')
     # version number should align with the branched version
     check_version = lambda version: (
       version.major == int(m.group(1)) and
@@ -78,7 +80,7 @@ settings = build_yaml['settings']
 top_version = Version(settings['version'])
 if not check_version(top_version):
   errors += 1
-  print warning % ('version', top_version)
+  print(warning % ('version', top_version))
 
 for tag, value in settings.iteritems():
   if re.match(r'^[a-z]+_version$', tag):
@@ -86,12 +88,14 @@ for tag, value in settings.iteritems():
     if tag != 'core_version':
       if value.major != top_version.major:
         errors += 1
-        print 'major version mismatch on %s: %d vs %d' % (tag, value.major, top_version.major)
+        print('major version mismatch on %s: %d vs %d' % (tag, value.major,
+                                                          top_version.major))
       if value.minor != top_version.minor:
         errors += 1
-        print 'minor version mismatch on %s: %d vs %d' % (tag, value.minor, top_version.minor)
+        print('minor version mismatch on %s: %d vs %d' % (tag, value.minor,
+                                                          top_version.minor))
     if not check_version(value):
       errors += 1
-      print warning % (tag, value)
+      print(warning % (tag, value))
 
 sys.exit(errors)
diff --git a/tools/run_tests/sanity/core_banned_functions.py b/tools/run_tests/sanity/core_banned_functions.py
index 6d9be2e5d4a..c1069ccfb84 100755
--- a/tools/run_tests/sanity/core_banned_functions.py
+++ b/tools/run_tests/sanity/core_banned_functions.py
@@ -29,6 +29,8 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+from __future__ import print_function
+
 import os
 import sys
 
@@ -60,7 +62,7 @@ for root, dirs, files in os.walk('src/core'):
     for banned, exceptions in BANNED_EXCEPT.items():
       if path in exceptions: continue
       if banned in text:
-        print 'Illegal use of "%s" in %s' % (banned, path)
+        print('Illegal use of "%s" in %s' % (banned, path))
         errors += 1
 
 assert errors == 0
diff --git a/tools/run_tests/start_port_server.py b/tools/run_tests/start_port_server.py
index e33ac12bd3b..bfd72222b66 100755
--- a/tools/run_tests/start_port_server.py
+++ b/tools/run_tests/start_port_server.py
@@ -39,8 +39,10 @@ The path to this file is called out in test/core/util/port.c, and printed as
 an error message to users.
 """
 
+from __future__ import print_function
+
 import python_utils.start_port_server as start_port_server
 
 start_port_server.start_port_server()
 
-print "Port server started successfully"
+print("Port server started successfully")
diff --git a/tools/run_tests/stress_test/run_on_gke.py b/tools/run_tests/stress_test/run_on_gke.py
index e2be76e245a..a2a5f42a2c6 100755
--- a/tools/run_tests/stress_test/run_on_gke.py
+++ b/tools/run_tests/stress_test/run_on_gke.py
@@ -27,6 +27,9 @@
 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+from __future__ import print_function
+
 import argparse
 import datetime
 import json
@@ -124,23 +127,24 @@ class DockerImage:
     return 'gcr.io/%s/%s' % (project_id, image_name)
 
   def build_image(self):
-    print 'Building docker image: %s (tag: %s)' % (self.image_name,
-                                                   self.tag_name)
+    print('Building docker image: %s (tag: %s)' % (self.image_name,
+                                                   self.tag_name))
     os.environ['INTEROP_IMAGE'] = self.image_name
     os.environ['INTEROP_IMAGE_REPOSITORY_TAG'] = self.tag_name
     os.environ['BASE_NAME'] = self.dockerfile_dir
     os.environ['BUILD_TYPE'] = self.build_type
-    print 'DEBUG: path: ', self.build_script_path
+    print('DEBUG: path: ', self.build_script_path)
     if subprocess.call(args=[self.build_script_path]) != 0:
-      print 'Error in building the Docker image'
+      print('Error in building the Docker image')
       return False
     return True
 
   def push_to_gke_registry(self):
     cmd = ['gcloud', 'docker', 'push', self.tag_name]
-    print 'Pushing %s to the GKE registry..' % self.tag_name
+    print('Pushing %s to the GKE registry..' % self.tag_name)
     if subprocess.call(args=cmd) != 0:
-      print 'Error in pushing the image %s to the GKE registry' % self.tag_name
+      print('Error in pushing the image %s to the GKE registry' %
+            self.tag_name)
       return False
     return True
 
@@ -199,11 +203,11 @@ class Gke:
       cmd = ['kubectl', 'proxy', '--port=%d' % port]
       self.p = subprocess.Popen(args=cmd)
       time.sleep(2)
-      print '\nStarted kubernetes proxy on port: %d' % port
+      print('\nStarted kubernetes proxy on port: %d' % port)
 
     def __del__(self):
       if self.p is not None:
-        print 'Shutting down Kubernetes proxy..'
+        print('Shutting down Kubernetes proxy..')
         self.p.kill()
 
   def __init__(self, project_id, run_id, dataset_id, summary_table_id,
@@ -253,7 +257,7 @@ class Gke:
 
     for pod_name in server_pod_spec.pod_names():
       server_env['POD_NAME'] = pod_name
-      print 'Creating server: %s' % pod_name
+      print('Creating server: %s' % pod_name)
       is_success = kubernetes_api.create_pod_and_service(
           'localhost',
           self.kubernetes_port,
@@ -267,11 +271,11 @@ class Gke:
           True  # Headless = True for server to that GKE creates a DNS record for pod_name
       )
       if not is_success:
-        print 'Error in launching server: %s' % pod_name
+        print('Error in launching server: %s' % pod_name)
         break
 
     if is_success:
-      print 'Successfully created server(s)'
+      print('Successfully created server(s)')
 
     return is_success
 
@@ -301,7 +305,7 @@ class Gke:
 
     for pod_name in client_pod_spec.pod_names():
       client_env['POD_NAME'] = pod_name
-      print 'Creating client: %s' % pod_name
+      print('Creating client: %s' % pod_name)
       is_success = kubernetes_api.create_pod_and_service(
           'localhost',
           self.kubernetes_port,
@@ -316,18 +320,18 @@ class Gke:
       )
 
       if not is_success:
-        print 'Error in launching client %s' % pod_name
+        print('Error in launching client %s' % pod_name)
         break
 
     if is_success:
-      print 'Successfully created all client(s)'
+      print('Successfully created all client(s)')
 
     return is_success
 
   def _delete_pods(self, pod_name_list):
     is_success = True
     for pod_name in pod_name_list:
-      print 'Deleting %s' % pod_name
+      print('Deleting %s' % pod_name)
       is_success = kubernetes_api.delete_pod_and_service(
           'localhost',
           self.kubernetes_port,
@@ -335,11 +339,11 @@ class Gke:
           pod_name)
 
       if not is_success:
-        print 'Error in deleting pod %s' % pod_name
+        print('Error in deleting pod %s' % pod_name)
         break
 
     if is_success:
-      print 'Successfully deleted all pods'
+      print('Successfully deleted all pods')
 
     return is_success
 
@@ -353,7 +357,7 @@ class Gke:
 class Config:
 
   def __init__(self, config_filename, gcp_project_id):
-    print 'Loading configuration...'
+    print('Loading configuration...')
     config_dict = self._load_config(config_filename)
 
     self.global_settings = self._parse_global_settings(config_dict,
@@ -367,7 +371,7 @@ class Config:
     self.client_pod_specs_dict = self._parse_client_pod_specs(
         config_dict, self.docker_images_dict, self.client_templates_dict,
         self.server_pod_specs_dict)
-    print 'Loaded Configuaration.'
+    print('Loaded Configuaration.')
 
   def _parse_global_settings(self, config_dict, gcp_project_id):
     global_settings_dict = config_dict['globalSettings']
@@ -540,8 +544,8 @@ def run_tests(config):
   # run id. This is useful in debugging when looking at records in Biq query)
   run_id = datetime.datetime.now().strftime('%Y_%m_%d_%H_%M_%S')
   dataset_id = '%s_%s' % (config.global_settings.dataset_id_prefix, run_id)
-  print 'Run id:', run_id
-  print 'Dataset id:', dataset_id
+  print('Run id:', run_id)
+  print('Dataset id:', dataset_id)
 
   bq_helper = BigQueryHelper(run_id, '', '',
                              config.global_settings.gcp_project_id, dataset_id,
@@ -557,7 +561,7 @@ def run_tests(config):
   is_success = True
 
   try:
-    print 'Launching servers..'
+    print('Launching servers..')
     for name, server_pod_spec in config.server_pod_specs_dict.iteritems():
       if not gke.launch_servers(server_pod_spec):
         is_success = False  # is_success is checked in the 'finally' block
@@ -579,11 +583,12 @@ def run_tests(config):
     start_time = datetime.datetime.now()
     end_time = start_time + datetime.timedelta(
         seconds=config.global_settings.test_duration_secs)
-    print 'Running the test until %s' % end_time.isoformat()
+    print('Running the test until %s' % end_time.isoformat())
 
     while True:
       if datetime.datetime.now() > end_time:
-        print 'Test was run for %d seconds' % config.global_settings.test_duration_secs
+        print('Test was run for %d seconds' %
+              config.global_settings.test_duration_secs)
         break
 
       # Check if either stress server or clients have failed (btw, the bq_helper
@@ -591,11 +596,12 @@ def run_tests(config):
       # have a failure status)
       if bq_helper.check_if_any_tests_failed():
         is_success = False
-        print 'Some tests failed.'
+        print('Some tests failed.')
         break  # Don't 'return' here. We still want to call bq_helper to print qps/summary tables
 
       # Tests running fine. Wait until next poll time to check the status
-      print 'Sleeping for %d seconds..' % config.global_settings.test_poll_interval_secs
+      print('Sleeping for %d seconds..' %
+            config.global_settings.test_poll_interval_secs)
       time.sleep(config.global_settings.test_poll_interval_secs)
 
     # Print BiqQuery tables

From 8e64d901fd7efd39868a889159329f41f74e3f9e Mon Sep 17 00:00:00 2001
From: Siddharth Shukla <siddharth.shukla@uber.com>
Date: Sun, 12 Mar 2017 19:50:18 +0100
Subject: [PATCH 9/9] Modify shebang on python scripts

Change shebangs to `#!/usr/bin/env python` instead of
`#!/usr/bin/env python2.7`.
---
 tools/run_tests/artifacts/artifact_targets.py             | 2 +-
 tools/run_tests/artifacts/distribtest_targets.py          | 2 +-
 tools/run_tests/artifacts/package_targets.py              | 2 +-
 tools/run_tests/performance/bq_upload_result.py           | 2 +-
 tools/run_tests/python_utils/antagonist.py                | 2 +-
 tools/run_tests/python_utils/filter_pull_request_tests.py | 2 +-
 tools/run_tests/python_utils/port_server.py               | 2 +-
 tools/run_tests/run_build_statistics.py                   | 2 +-
 tools/run_tests/run_interop_tests.py                      | 2 +-
 tools/run_tests/run_microbenchmark.py                     | 2 +-
 tools/run_tests/run_performance_tests.py                  | 2 +-
 tools/run_tests/run_stress_tests.py                       | 2 +-
 tools/run_tests/run_tests_matrix.py                       | 2 +-
 tools/run_tests/sanity/check_sources_and_headers.py       | 2 +-
 tools/run_tests/sanity/check_test_filtering.py            | 2 +-
 tools/run_tests/sanity/check_version.py                   | 2 +-
 tools/run_tests/sanity/core_banned_functions.py           | 2 +-
 tools/run_tests/stress_test/print_summary.py              | 2 +-
 tools/run_tests/stress_test/run_on_gke.py                 | 2 +-
 tools/run_tests/task_runner.py                            | 2 +-
 20 files changed, 20 insertions(+), 20 deletions(-)

diff --git a/tools/run_tests/artifacts/artifact_targets.py b/tools/run_tests/artifacts/artifact_targets.py
index e0658f4678d..04702baccae 100644
--- a/tools/run_tests/artifacts/artifact_targets.py
+++ b/tools/run_tests/artifacts/artifact_targets.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2016, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/artifacts/distribtest_targets.py b/tools/run_tests/artifacts/distribtest_targets.py
index a7535b38521..90bbde83cf4 100644
--- a/tools/run_tests/artifacts/distribtest_targets.py
+++ b/tools/run_tests/artifacts/distribtest_targets.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2016, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/artifacts/package_targets.py b/tools/run_tests/artifacts/package_targets.py
index d490f571c37..2547f2073cf 100644
--- a/tools/run_tests/artifacts/package_targets.py
+++ b/tools/run_tests/artifacts/package_targets.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2016, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/performance/bq_upload_result.py b/tools/run_tests/performance/bq_upload_result.py
index e2e1393509e..3bac1199a7b 100755
--- a/tools/run_tests/performance/bq_upload_result.py
+++ b/tools/run_tests/performance/bq_upload_result.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2016, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/python_utils/antagonist.py b/tools/run_tests/python_utils/antagonist.py
index 857addfb386..111839ccf93 100755
--- a/tools/run_tests/python_utils/antagonist.py
+++ b/tools/run_tests/python_utils/antagonist.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2015, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/python_utils/filter_pull_request_tests.py b/tools/run_tests/python_utils/filter_pull_request_tests.py
index 041e3491627..e0133762959 100644
--- a/tools/run_tests/python_utils/filter_pull_request_tests.py
+++ b/tools/run_tests/python_utils/filter_pull_request_tests.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2015, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/python_utils/port_server.py b/tools/run_tests/python_utils/port_server.py
index e9b3f7ff795..dbd32efc0e8 100755
--- a/tools/run_tests/python_utils/port_server.py
+++ b/tools/run_tests/python_utils/port_server.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2015, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/run_build_statistics.py b/tools/run_tests/run_build_statistics.py
index e33e01e7034..dd11a45e789 100755
--- a/tools/run_tests/run_build_statistics.py
+++ b/tools/run_tests/run_build_statistics.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2016, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/run_interop_tests.py b/tools/run_tests/run_interop_tests.py
index ace142ed8ad..29d5a9aaa00 100755
--- a/tools/run_tests/run_interop_tests.py
+++ b/tools/run_tests/run_interop_tests.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2015, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/run_microbenchmark.py b/tools/run_tests/run_microbenchmark.py
index 94711109680..57b2636e569 100755
--- a/tools/run_tests/run_microbenchmark.py
+++ b/tools/run_tests/run_microbenchmark.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2017, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/run_performance_tests.py b/tools/run_tests/run_performance_tests.py
index c79f47a3175..35d20be5b75 100755
--- a/tools/run_tests/run_performance_tests.py
+++ b/tools/run_tests/run_performance_tests.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2016, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/run_stress_tests.py b/tools/run_tests/run_stress_tests.py
index 3a2661a9aa6..4eea02118e5 100755
--- a/tools/run_tests/run_stress_tests.py
+++ b/tools/run_tests/run_stress_tests.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2015, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/run_tests_matrix.py b/tools/run_tests/run_tests_matrix.py
index 191228e4db7..b9a9bd52f64 100755
--- a/tools/run_tests/run_tests_matrix.py
+++ b/tools/run_tests/run_tests_matrix.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2015, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/sanity/check_sources_and_headers.py b/tools/run_tests/sanity/check_sources_and_headers.py
index 0bb92fda8b5..f2e0bfeb3d4 100755
--- a/tools/run_tests/sanity/check_sources_and_headers.py
+++ b/tools/run_tests/sanity/check_sources_and_headers.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2015, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/sanity/check_test_filtering.py b/tools/run_tests/sanity/check_test_filtering.py
index aceee6d4d72..ba03f112092 100755
--- a/tools/run_tests/sanity/check_test_filtering.py
+++ b/tools/run_tests/sanity/check_test_filtering.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 
 # Copyright 2016, Google Inc.
 # All rights reserved.
diff --git a/tools/run_tests/sanity/check_version.py b/tools/run_tests/sanity/check_version.py
index d8162fb3c57..d247260dbbb 100755
--- a/tools/run_tests/sanity/check_version.py
+++ b/tools/run_tests/sanity/check_version.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 
 # Copyright 2016, Google Inc.
 # All rights reserved.
diff --git a/tools/run_tests/sanity/core_banned_functions.py b/tools/run_tests/sanity/core_banned_functions.py
index c1069ccfb84..c3c3cbec767 100755
--- a/tools/run_tests/sanity/core_banned_functions.py
+++ b/tools/run_tests/sanity/core_banned_functions.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 
 # Copyright 2016, Google Inc.
 # All rights reserved.
diff --git a/tools/run_tests/stress_test/print_summary.py b/tools/run_tests/stress_test/print_summary.py
index cb1a33961e4..6f4ada2f4fd 100755
--- a/tools/run_tests/stress_test/print_summary.py
+++ b/tools/run_tests/stress_test/print_summary.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2016, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/stress_test/run_on_gke.py b/tools/run_tests/stress_test/run_on_gke.py
index a2a5f42a2c6..b190ebde7a4 100755
--- a/tools/run_tests/stress_test/run_on_gke.py
+++ b/tools/run_tests/stress_test/run_on_gke.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2015-2016, Google Inc.
 # All rights reserved.
 #
diff --git a/tools/run_tests/task_runner.py b/tools/run_tests/task_runner.py
index fdc46682223..0ec7efbbee6 100755
--- a/tools/run_tests/task_runner.py
+++ b/tools/run_tests/task_runner.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 # Copyright 2016, Google Inc.
 # All rights reserved.
 #