src/tools/perf/measurements/loading_profile.py

   1 # Copyright 2013 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 os
   6 import tempfile
   7
   8 from metrics import loading
   9 from telemetry.core.platform.profiler import perf_profiler
  10 from telemetry.page import page_test
  11 from telemetry.value import scalar
  12
  13
  14 class LoadingProfile(page_test.PageTest):
  15   options = {'page_repeat': 2}
  16
  17   def __init__(self):
  18     super(LoadingProfile, self).__init__(discard_first_result=True)
  19
  20   def CustomizeBrowserOptions(self, options):
  21     if not perf_profiler.PerfProfiler.is_supported(browser_type='any'):
  22       raise Exception('This measurement is not supported on this platform')
  23
  24     perf_profiler.PerfProfiler.CustomizeBrowserOptions(
  25         browser_type='any', options=options)
  26
  27   def WillNavigateToPage(self, page, tab):
  28     tab.browser.StartProfiling(perf_profiler.PerfProfiler.name(),
  29                                os.path.join(tempfile.mkdtemp(),
  30                                             page.file_safe_name))
  31
  32   def ValidateAndMeasurePage(self, page, tab, results):
  33     # In current telemetry tests, all tests wait for DocumentComplete state,
  34     # but we need to wait for the load event.
  35     tab.WaitForJavaScriptExpression('performance.timing.loadEventStart', 300)
  36
  37     profile_files = tab.browser.StopProfiling()
  38
  39     loading.LoadingMetric().AddResults(tab, results)
  40
  41     profile_file = None
  42     for profile_file in profile_files:
  43       if 'renderer' in profile_file:
  44         break
  45
  46     for function, period in perf_profiler.PerfProfiler.GetTopSamples(
  47         profile_file, 10).iteritems():
  48       results.AddValue(scalar.ScalarValue(
  49           results.current_page, function.replace('.', '_'), 'period', period))