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 """The tab switching measurement. 6 7 This measurement opens pages in different tabs. After all the tabs have opened, 8 it cycles through each tab in sequence, and records a histogram of the time 9 between when a tab was first requested to be shown, and when it was painted. 10 Power usage is also measured. 11 """ 12 13 import time 14 15 from metrics import power 16 from telemetry.core import util 17 from telemetry.page import page_test 18 from telemetry.value import histogram 19 from telemetry.value import histogram_util 20 21 # TODO: Revisit this test once multitab support is finalized. 22 23 class TabSwitching(page_test.PageTest): 24 25 # Amount of time to measure, in seconds. 26 SAMPLE_TIME = 30 27 28 def __init__(self): 29 super(TabSwitching, self).__init__() 30 self._first_page_in_pageset = True 31 self._power_metric = None 32 33 def CustomizeBrowserOptions(self, options): 34 options.AppendExtraBrowserArgs([ 35 '--enable-stats-collection-bindings' 36 ]) 37 # Enable background networking so we can test its impact on power usage. 38 options.disable_background_networking = False 39 power.PowerMetric.CustomizeBrowserOptions(options) 40 41 def WillStartBrowser(self, platform): 42 self._first_page_in_pageset = True 43 self._power_metric = power.PowerMetric(platform, TabSwitching.SAMPLE_TIME) 44 45 def TabForPage(self, page, browser): 46 if self._first_page_in_pageset: 47 # The initial browser window contains a single tab, navigate that tab 48 # rather than creating a new one. 49 self._first_page_in_pageset = False 50 return browser.tabs[0] 51 52 return browser.tabs.New() 53 54 def StopBrowserAfterPage(self, browser, page): 55 # Restart the browser after the last page in the pageset. 56 return len(browser.tabs) >= len(page.page_set.pages) 57 58 def ValidateAndMeasurePage(self, page, tab, results): 59 """On the last tab, cycle through each tab that was opened and then record 60 a single histogram for the tab switching metric.""" 61 if len(tab.browser.tabs) != len(page.page_set.pages): 62 return 63 64 # Measure power usage of tabs after quiescence. 65 util.WaitFor(tab.HasReachedQuiescence, 60) 66 67 if tab.browser.platform.CanMonitorPower(): 68 self._power_metric.Start(page, tab) 69 time.sleep(TabSwitching.SAMPLE_TIME) 70 self._power_metric.Stop(page, tab) 71 self._power_metric.AddResults(tab, results,) 72 73 histogram_name = 'MPArch.RWH_TabSwitchPaintDuration' 74 histogram_type = histogram_util.BROWSER_HISTOGRAM 75 display_name = 'MPArch_RWH_TabSwitchPaintDuration' 76 first_histogram = histogram_util.GetHistogram( 77 histogram_type, histogram_name, tab) 78 prev_histogram = first_histogram 79 80 for i in xrange(len(tab.browser.tabs)): 81 t = tab.browser.tabs[i] 82 t.Activate() 83 def _IsDone(): 84 cur_histogram = histogram_util.GetHistogram( 85 histogram_type, histogram_name, tab) 86 diff_histogram = histogram_util.SubtractHistogram( 87 cur_histogram, prev_histogram) 88 return diff_histogram 89 util.WaitFor(_IsDone, 30) 90 prev_histogram = histogram_util.GetHistogram( 91 histogram_type, histogram_name, tab) 92 93 last_histogram = histogram_util.GetHistogram( 94 histogram_type, histogram_name, tab) 95 diff_histogram = histogram_util.SubtractHistogram(last_histogram, 96 first_histogram) 97 98 results.AddSummaryValue( 99 histogram.HistogramValue(None, display_name, 'ms', 100 raw_value_json=diff_histogram, 101 important=False)) 102
