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 json 6 7 from telemetry.page import page_measurement 8 9 class Startup(page_measurement.PageMeasurement): 10 """Performs a measurement of Chromium's startup performance. 11 12 This test must be invoked with either --warm or --cold on the command line. A 13 cold start means none of the Chromium files are in the disk cache. A warm 14 start assumes the OS has already cached much of Chromium's content. For warm 15 tests, you should repeat the page set to ensure it's cached. 16 """ 17 18 HISTOGRAMS_TO_RECORD = { 19 'messageloop_start_time' : 20 'Startup.BrowserMessageLoopStartTimeFromMainEntry', 21 'window_display_time' : 'Startup.BrowserWindowDisplay', 22 'open_tabs_time' : 'Startup.BrowserOpenTabs'} 23 24 def __init__(self): 25 super(Startup, self).__init__(needs_browser_restart_after_each_run=True) 26 self._cold = False 27 28 def AddCommandLineOptions(self, parser): 29 parser.add_option('--cold', action='store_true', 30 help='Clear the OS disk cache before performing the test') 31 parser.add_option('--warm', action='store_true', 32 help='Start up with everything already cached') 33 34 def CustomizeBrowserOptions(self, options): 35 # TODO: Once the bots start running benchmarks, enforce that either --warm 36 # or --cold is explicitly specified. 37 # assert options.warm != options.cold, \ 38 # "You must specify either --warm or --cold" 39 self._cold = options.cold 40 41 if self._cold: 42 options.clear_sytem_cache_for_browser_and_profile_on_start = True 43 else: 44 self.discard_first_result = True 45 46 options.AppendExtraBrowserArg('--enable-stats-collection-bindings') 47 48 # Old commandline flags used for reference builds. 49 options.AppendExtraBrowserArg('--dom-automation') 50 options.AppendExtraBrowserArg( 51 '--reduce-security-for-dom-automation-tests') 52 53 def MeasurePage(self, page, tab, results): 54 # TODO(jeremy): Remove references to 55 # domAutomationController.getBrowserHistogram when we update the reference 56 # builds. 57 get_histogram_js = ('(window.statsCollectionController ?' 58 'statsCollectionController :' 59 'domAutomationController).getBrowserHistogram("%s")') 60 61 for display_name, histogram_name in self.HISTOGRAMS_TO_RECORD.iteritems(): 62 result = tab.EvaluateJavaScript(get_histogram_js % histogram_name) 63 result = json.loads(result) 64 measured_time = 0 65 66 if 'sum' in result: 67 # For all the histograms logged here, there's a single entry so sum 68 # is the exact value for that entry. 69 measured_time = result['sum'] 70 elif 'buckets' in result: 71 measured_time = \ 72 (result['buckets'][0]['high'] + result['buckets'][0]['low']) / 2 73 74 results.Add(display_name, 'ms', measured_time) 75
