add some comments

src/proto/grpc/testing/control.proto

@@ -242,6 +242,7 @@ message ScenarioResultSummary
   double successful_requests_per_second = 13;
   double failed_requests_per_second = 14;
 
+  // Number of polls called inside completion queue per request
   double client_polls_per_request = 15;
   double server_polls_per_request = 16;
 }

src/proto/grpc/testing/stats.proto

@@ -48,6 +48,7 @@ message ServerStats {
   // change in idle time of the server (data from proc/stat)
   uint64 idle_cpu_time = 5;
 
+  // Number of polls called inside completion queue
   uint64 cq_poll_count = 6;
 }
 
@@ -84,5 +85,6 @@ message ClientStats {
   // Number of failed requests (one row per status code seen)
   repeated RequestResultCount request_results = 5;
 
+  // Number of polls called inside completion queue
   uint64 cq_poll_count = 6;
 }

test/cpp/microbenchmarks/fullstack_fixtures.h

@@ -100,17 +100,10 @@ class FullstackFixture : public BaseFixture {
     }
   }
 
-  void Finish(benchmark::State& state) {
+  void AddToLabel(std::ostream& out, benchmark::State& state) {
-    std::ostringstream out;
+    BaseFixture::AddToLabel(out, state);
-    AddToLabel(out, state);
+    out << " polls/iter:"
-    AppendToLabel(
+        << (double)grpc_get_cq_poll_num(this->cq()->cq()) / state.iterations();
-        out, "polls/iter",
-        (double)grpc_get_cq_poll_num(this->cq()->cq()) / state.iterations());
-    auto label = out.str();
-    if (label.length() && label[0] == ' ') {
-      label = label.substr(1);
-    }
-    state.SetLabel(label);
   }
 
   ServerCompletionQueue* cq() { return cq_.get(); }
@@ -225,17 +218,10 @@ class EndpointPairFixture : public BaseFixture {
     }
   }
 
-  void Finish(benchmark::State& state) {
+  void AddToLabel(std::ostream& out, benchmark::State& state) {
-    std::ostringstream out;
+    BaseFixture::AddToLabel(out, state);
-    AddToLabel(out, state);
+    out << " polls/iter:"
-    AppendToLabel(
+        << (double)grpc_get_cq_poll_num(this->cq()->cq()) / state.iterations();
-        out, "polls/iter",
-        (double)grpc_get_cq_poll_num(this->cq()->cq()) / state.iterations());
-    auto label = out.str();
-    if (label.length() && label[0] == ' ') {
-      label = label.substr(1);
-    }
-    state.SetLabel(label);
   }
 
   ServerCompletionQueue* cq() { return cq_.get(); }
@@ -271,7 +257,7 @@ class InProcessCHTTP2 : public EndpointPairFixture {
   void AddToLabel(std::ostream& out, benchmark::State& state) {
     EndpointPairFixture::AddToLabel(out, state);
     out << " writes/iter:"
-        << ((double)stats_.num_writes / (double)state.iterations());
+        << (double)stats_.num_writes / (double)state.iterations();
   }
 
  private:

test/cpp/microbenchmarks/helpers.cc

@@ -67,8 +67,3 @@ void TrackCounters::AddToLabel(std::ostream &out, benchmark::State &state) {
           (double)state.iterations());
 #endif
 }
-
-void TrackCounters::AppendToLabel(std::ostream &out, std::string metric,
-                                  double value) {
-  out << " " << key << ":" << value;
-}

test/cpp/microbenchmarks/helpers.h

@@ -80,8 +80,6 @@ class TrackCounters {
  public:
   virtual void Finish(benchmark::State& state);
   virtual void AddToLabel(std::ostream& out, benchmark::State& state);
-  virtual void AppendToLabel(std::ostream& out, std::string metric,
-                             double value);
 
  private:
 #ifdef GPR_LOW_LEVEL_COUNTERS

test/cpp/qps/report.h

@@ -76,7 +76,7 @@ class Reporter {
   /** Reports server cpu usage. */
   virtual void ReportCpuUsage(const ScenarioResult& result) = 0;
 
-  /** Reports server cpu usage. */
+  /** Reports client and server poll usage inside completion queue. */
   virtual void ReportPollCount(const ScenarioResult& result) = 0;
 
  private: