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