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 histogram_util 16 from metrics import power 17 from telemetry.core import util 18 from telemetry.page import page_measurement 19 from telemetry.value import histogram 20 21 # TODO: Revisit this test once multitab support is finalized. 22 23 class TabSwitching(page_measurement.PageMeasurement): 24 def __init__(self): 25 super(TabSwitching, self).__init__() 26 self._first_page_in_pageset = True 27 self._power_metric = power.PowerMetric() 28 29 def CustomizeBrowserOptions(self, options): 30 options.AppendExtraBrowserArgs([ 31 '--enable-stats-collection-bindings' 32 ]) 33 power.PowerMetric.CustomizeBrowserOptions(options) 34 35 def DidStartBrowser(self, browser): 36 self._first_page_in_pageset = True 37 38 def TabForPage(self, page, browser): 39 if self._first_page_in_pageset: 40 # The initial browser window contains a single tab, navigate that tab 41 # rather than creating a new one. 42 self._first_page_in_pageset = False 43 return browser.tabs[0] 44 45 return browser.tabs.New() 46 47 def StopBrowserAfterPage(self, browser, page): 48 # Restart the browser after the last page in the pageset. 49 return len(browser.tabs) >= len(page.page_set.pages) 50 51 def MeasurePage(self, page, tab, results): 52 """On the last tab, cycle through each tab that was opened and then record 53 a single histogram for the tab switching metric.""" 54 if len(tab.browser.tabs) != len(page.page_set.pages): 55 return 56 57 # Measure power usage of tabs after quiescence. 58 util.WaitFor(tab.HasReachedQuiescence, 60) 59 60 self._power_metric.Start(page, tab) 61 time.sleep(60) 62 self._power_metric.Stop(page, tab) 63 self._power_metric.AddResults(tab, results,) 64 65 histogram_name = 'MPArch.RWH_TabSwitchPaintDuration' 66 histogram_type = histogram_util.BROWSER_HISTOGRAM 67 display_name = 'MPArch_RWH_TabSwitchPaintDuration' 68 first_histogram = histogram_util.GetHistogram( 69 histogram_type, histogram_name, tab) 70 prev_histogram = first_histogram 71 72 for i in xrange(len(tab.browser.tabs)): 73 t = tab.browser.tabs[i] 74 t.Activate() 75 def _IsDone(): 76 cur_histogram = histogram_util.GetHistogram( 77 histogram_type, histogram_name, tab) 78 diff_histogram = histogram_util.SubtractHistogram( 79 cur_histogram, prev_histogram) 80 return diff_histogram 81 util.WaitFor(_IsDone, 30) 82 prev_histogram = histogram_util.GetHistogram( 83 histogram_type, histogram_name, tab) 84 85 last_histogram = histogram_util.GetHistogram( 86 histogram_type, histogram_name, tab) 87 diff_histogram = histogram_util.SubtractHistogram(last_histogram, 88 first_histogram) 89 90 results.AddSummaryValue( 91 histogram.HistogramValue(None, display_name, '', 92 raw_value_json=diff_histogram, 93 important=False)) 94
