tools/perf/perf_tools/loading_benchmark.py

   1 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4
   5 import collections
   6
   7 from telemetry.core import util
   8 from telemetry.page import page_benchmark
   9
  10 class LoadingBenchmark(page_benchmark.PageBenchmark):
  11   @property
  12   def results_are_the_same_on_every_page(self):
  13     return False
  14
  15   def WillNavigateToPage(self, page, tab):
  16     tab.StartTimelineRecording()
  17
  18   def MeasurePage(self, page, tab, results):
  19     # In current telemetry tests, all tests wait for DocumentComplete state,
  20     # but we need to wait for the load event.
  21     def IsLoaded():
  22       return bool(tab.EvaluateJavaScript('performance.timing.loadEventStart'))
  23     util.WaitFor(IsLoaded, 30)
  24
  25     # TODO(nduca): when crbug.com/168431 is fixed, modify the page sets to
  26     # recognize loading as a toplevel action.
  27     tab.StopTimelineRecording()
  28
  29     load_timings = tab.EvaluateJavaScript('window.performance.timing')
  30     load_time_ms = (
  31       float(load_timings['loadEventStart']) -
  32       load_timings['navigationStart'])
  33     dom_content_loaded_time_ms = (
  34       float(load_timings['domContentLoadedEventStart']) -
  35       load_timings['navigationStart'])
  36     results.Add('load_time', 'ms', load_time_ms)
  37     results.Add('dom_content_loaded_time', 'ms',
  38                 dom_content_loaded_time_ms)
  39
  40     events = tab.timeline_model.GetAllEvents()
  41
  42     events_by_name = collections.defaultdict(list)
  43     for e in events:
  44       events_by_name[e.name].append(e)
  45
  46     for key, group in events_by_name.items():
  47       times = [e.self_time_ms for e in group]
  48       total = sum(times)
  49       biggest_jank = max(times)
  50       results.Add(key, 'ms', total)
  51       results.Add(key + '_max', 'ms', biggest_jank)
  52       results.Add(key + '_avg', 'ms', total / len(times))