tools/perf/measurements/session_restore.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 from telemetry.core import util
   6 from telemetry.value import histogram
   7 from telemetry.value import histogram_util
   8
   9 from measurements import startup
  10 from metrics import cpu
  11
  12
  13 _HISTOGRAMS = [
  14     {
  15         'name': 'SessionRestore.ForegroundTabFirstLoaded',
  16         'display_name': 'SessionRestore_ForegroundTabFirstLoaded',
  17     },
  18     {
  19         'name': 'SessionRestore.AllTabsLoaded',
  20         'display_name': 'SessionRestore_AllTabsLoaded',
  21     },
  22 ]
  23
  24 class SessionRestore(startup.Startup):
  25   """Performs a measurement of Chromium's Session restore performance.
  26
  27   This test is meant to be run against a generated profile.
  28   This test inherits support for the 'cold' option -
  29   see startup.py for details.
  30   """
  31
  32   def __init__(self, cold=False):
  33     super(SessionRestore, self).__init__(cold=cold)
  34     self.close_tabs_before_run = False
  35     self._cpu_metric = None
  36
  37   def CustomizeBrowserOptions(self, options):
  38     super(SessionRestore, self).CustomizeBrowserOptions(options)
  39     histogram_util.CustomizeBrowserOptions(options)
  40     options.AppendExtraBrowserArgs([
  41         '--restore-last-session'
  42     ])
  43
  44     # Prevent about:blank from being the foreground tab, as that prevents
  45     # accurately measuring foreground first load time for session restore.
  46     options.startup_url = ''
  47
  48   def TabForPage(self, page, browser):
  49     # Detect that the session restore has completed.
  50     util.WaitFor(lambda: browser.tabs and
  51                  histogram_util.GetHistogramCount(
  52                      histogram_util.BROWSER_HISTOGRAM,
  53                      'SessionRestore.AllTabsLoaded',
  54                      browser.foreground_tab),
  55                  60)
  56     return browser.foreground_tab
  57
  58   def RunNavigateSteps(self, page, tab):
  59     # Overridden so that no page navigation occurs.
  60     pass
  61
  62   def DidStartBrowser(self, browser):
  63     self._cpu_metric = cpu.CpuMetric(browser)
  64     self._cpu_metric.Start(None, None)
  65
  66   def ValidateAndMeasurePage(self, page, tab, results):
  67     tab.WaitForDocumentReadyStateToBeComplete()
  68     super(SessionRestore, self).ValidateAndMeasurePage(page, tab, results)
  69
  70     # Record CPU usage from browser start to when the foreground page is loaded.
  71     self._cpu_metric.Stop(None, None)
  72     self._cpu_metric.AddResults(tab, results, 'cpu_utilization')
  73
  74     for h in _HISTOGRAMS:
  75       histogram_data = histogram_util.GetHistogram(
  76           histogram_util.BROWSER_HISTOGRAM, h['name'], tab)
  77
  78       results.AddValue(histogram.HistogramValue(
  79           page, h['display_name'], 'ms', raw_value_json=histogram_data,
  80           important=False))