Report network stats in the scroll performance tests

remoting/test/protocol_perftest.cc

Index: remoting/test/protocol_perftest.cc
diff --git a/remoting/test/protocol_perftest.cc b/remoting/test/protocol_perftest.cc
index 6b451bb65212680054e38b893c8fa18984e29163..b5c0fc952eb2c70839845dbf88282bcbc452137f 100644
--- a/remoting/test/protocol_perftest.cc
+++ b/remoting/test/protocol_perftest.cc
@@ -311,6 +311,7 @@ class ProtocolPerfTest
 
     std::unique_ptr<FakePortAllocatorFactory> port_allocator_factory(
         new FakePortAllocatorFactory(fake_network_dispatcher_));
+    client_socket_factory_ = port_allocator_factory->socket_factory();
     port_allocator_factory->socket_factory()->SetBandwidth(
         GetParam().bandwidth, GetParam().max_buffers);
     port_allocator_factory->socket_factory()->SetLatency(
@@ -368,6 +369,8 @@ class ProtocolPerfTest
   std::unique_ptr<SoftwareVideoRenderer> video_renderer_;
   std::unique_ptr<ChromotingClient> client_;
 
+  FakePacketSocketFactory* client_socket_factory_;
+
   std::unique_ptr<base::RunLoop> connecting_loop_;
   std::unique_ptr<base::RunLoop> waiting_frames_loop_;
 
@@ -554,6 +557,8 @@ void ProtocolPerfTest::MeasureScrollPerformance(bool use_webrtc) {
     ++warm_up_frames;
   }
 
+  client_socket_factory_->ResetStats();
+
   // Run the test for 2 seconds.
   const base::TimeDelta kTestTime = base::TimeDelta::FromSeconds(2);
 
@@ -584,6 +589,9 @@ void ProtocolPerfTest::MeasureScrollPerformance(bool use_webrtc) {
   VLOG(0) << "Bandwidth utilization: "
           << 100 * total_size / (total_time.InSecondsF() * GetParam().bandwidth)
           << "%";
+  VLOG(0) << "Average host->client network latency + bufferbloat: "
+          << client_socket_factory_->GetAverageDelay().InMilliseconds()

[Irfan, 2016/09/27 17:52:07]

It appears a packet is dropped when the buffer overflows in the leaky bucket and
this does not get taken into account.

If you want true impact of the buffer + latency, it seems we should either
measure the packet loss as a result of the buffer drop or take into account the
latency of these dropped packets (MAX) WDYT ?

[Sergey Ulanov, 2016/09/27 20:21:35]

This is good point. Problem is that the fake network layer doesn't know when
packets are resent, so I don't see how it could measure impact of dropped
packets on total latency.
The goal here is to measure impact of buffer bloat, not the network latency
overall. Updated how this value is reported. Also updated this code to report
packet drop rate.

+          << " ms";
 }
 
 TEST_P(ProtocolPerfTest, ScrollPerformanceIce) {