Happening in this build: https://ci.chromium.org/buildbot/chromium.perf/win-10-perf/96

Log:
https://chrome-isolated.appspot.com/browse?namespace=default-gzip&digest=0b1ae68c6f9cf5dc281f13967a1c8a256b47d841&as=v8.runtime_stats.top_25%5Cbenchmark_log.txt

There was a socket error when collect tracing, then followed by AssertionError

First error:
Traceback (most recent call last):
  _RunStoryAndProcessErrorIfNeeded at c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\story_runner.py:152
    test.DidRunStory(state.platform, results)
  DidRunStory at c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\web_perf\timeline_based_measurement.py:288
    trace_result, _ = platform.tracing_controller.StopTracing()
  StopTracing at c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\core\tracing_controller.py:53
    return self._tracing_controller_backend.StopTracing()
  StopTracing at c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\platform\tracing_controller_backend.py:157
    '\n'.join(raised_exception_messages))
TracingException: Exceptions raised when trying to stop tracing:
Traceback (most recent call last):
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\platform\tracing_controller_backend.py", line 135, in StopTracing
    agent.StopAgentTracing()
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\platform\tracing_agent\chrome_tracing_agent.py", line 231, in StopAgentTracing
    '\n'.join(raised_exception_messages))
ChromeTracingStoppedError: Exceptions raised when trying to stop Chrome devtool tracing:
Error when trying to stop Chrome tracing
            on devtools at port 57063:
Traceback (most recent call last):
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\platform\tracing_agent\chrome_tracing_agent.py", line 213, in StopAgentTracing
    client.StopChromeTracing()
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\backends\chrome_inspector\devtools_client_backend.py", line 463, in StopChromeTracing
    backend.AddTimelineMarker('first-renderer-thread')
  File "c:\b\s\w\ir\third_party\catapult\common\py_trace_event\py_trace_event\trace_event_impl\decorators.py", line 75, in traced_function
    return func(*args, **kwargs)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\backends\chrome_inspector\inspector_backend.py", line 310, in AddTimelineMarker
    marker=str(marker))
  File "c:\b\s\w\ir\third_party\catapult\common\py_trace_event\py_trace_event\trace_event_impl\decorators.py", line 75, in traced_function
    return func(*args, **kwargs)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\backends\chrome_inspector\inspector_backend.py", line 41, in Inner
    inspector_backend._ConvertExceptionFromInspectorWebsocket(e)
  File "c:\b\s\w\ir\third_party\catapult\common\py_trace_event\py_trace_event\trace_event_impl\decorators.py", line 75, in traced_function
    return func(*args, **kwargs)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\backends\chrome_inspector\inspector_backend.py", line 38, in Inner
    return func(inspector_backend, *args, **kwargs)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\backends\chrome_inspector\inspector_backend.py", line 225, in ExecuteJavaScript
    self._runtime.Execute(statement, context_id, timeout)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\backends\chrome_inspector\inspector_runtime.py", line 20, in Execute
    self.Evaluate(expr + '; 0;', context_id, timeout)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\backends\chrome_inspector\inspector_runtime.py", line 44, in Evaluate
    res = self._inspector_websocket.SyncRequest(request, timeout)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\backends\chrome_inspector\inspector_websocket.py", line 116, in SyncRequest
    res = self._Receive(timeout)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\backends\chrome_inspector\inspector_websocket.py", line 155, in _Receive
    data = self._socket.recv()
  File "c:\b\s\w\ir\third_party\catapult\telemetry\third_party\websocket-client\websocket\_core.py", line 293, in recv
    opcode, data = self.recv_data()
  File "c:\b\s\w\ir\third_party\catapult\telemetry\third_party\websocket-client\websocket\_core.py", line 310, in recv_data
    opcode, frame = self.recv_data_frame(control_frame)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\third_party\websocket-client\websocket\_core.py", line 323, in recv_data_frame
    frame = self.recv_frame()
  File "c:\b\s\w\ir\third_party\catapult\telemetry\third_party\websocket-client\websocket\_core.py", line 357, in recv_frame
    return self.frame_buffer.recv_frame()
  File "c:\b\s\w\ir\third_party\catapult\telemetry\third_party\websocket-client\websocket\_abnf.py", line 336, in recv_frame
    self.recv_header()
  File "c:\b\s\w\ir\third_party\catapult\telemetry\third_party\websocket-client\websocket\_abnf.py", line 286, in recv_header
    header = self.recv_strict(2)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\third_party\websocket-client\websocket\_abnf.py", line 371, in recv_strict
    bytes_ = self.recv(min(16384, shortage))
  File "c:\b\s\w\ir\third_party\catapult\telemetry\third_party\websocket-client\websocket\_core.py", line 427, in _recv
    return recv(self.sock, bufsize)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\third_party\websocket-client\websocket\_socket.py", line 83, in recv
    raise WebSocketTimeoutException(message)
TimeoutException: 
********************************************************************************
(c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\backends\chrome_inspector\inspector_backend.py:496 _ConvertExceptionFromInspectorWebsocket) The app is probably crashed:

Found Minidump: False


Second error:

(ERROR) 2018-08-04 04:28:15,072 story_runner.ProcessError:100  Unhandleable error. Benchmark run will be interrupted
Traceback (most recent call last):
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\story_runner.py", line 117, in _RunStoryAndProcessErrorIfNeeded
    test.WillRunStory(state.platform)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\web_perf\timeline_based_measurement.py", line 255, in WillRunStory
    platform.tracing_controller.StartTracing(self._tbm_options.config)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\core\tracing_controller.py", line 43, in StartTracing
    self._tracing_controller_backend.StartTracing(tracing_config, timeout)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\platform\tracing_controller_backend.py", line 108, in StartTracing
    if agent.StartAgentTracing(config, timeout):
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\platform\tracing_agent\chrome_tracing_agent.py", line 124, in StartAgentTracing
    started_devtools_tracing = self._StartDevToolsTracing(config, timeout)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\platform\tracing_agent\chrome_tracing_agent.py", line 101, in _StartDevToolsTracing
    client.StartChromeTracing(config, timeout)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\backends\chrome_inspector\devtools_client_backend.py", line 452, in StartChromeTracing
    trace_config.chrome_trace_config, timeout)
  File "c:\b\s\w\ir\third_party\catapult\telemetry\telemetry\internal\backends\chrome_inspector\tracing_backend.py", line 117, in StartTracing
    assert not self._can_collect_data, 'Data not collected from last trace.'
AssertionError: Data not collected from last trace.