chrome/browser/metrics/first_web_contents_profiler.cc

   1 // Copyright 2014 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 #if !defined(OS_ANDROID)
   6
   7 #include "chrome/browser/metrics/first_web_contents_profiler.h"
   8
   9 #include "base/metrics/histogram_macros.h"
  10 #include "base/process/process_info.h"
  11 #include "base/time/time.h"
  12 #include "chrome/browser/ui/browser.h"
  13 #include "chrome/browser/ui/browser_iterator.h"
  14 #include "chrome/browser/ui/tabs/tab_strip_model.h"
  15 #include "chrome/common/chrome_version_info.h"
  16
  17 namespace {
  18
  19 const int kHistogramMinTimeMilliseconds = 200;
  20 const int kHistogramMaxTimeSeconds = 45;
  21
  22 // There is a lot of noise in the dev channel. One possible cause is that the
  23 // bucket ranges are too wide. The bucket count is chosen such that the size of
  24 // the bucket is 1% of its minimum. Notice that this also means that
  25 // subsequent buckets will satisfy Min(bucket N + 1) / Min(bucket N) = 1.01.
  26 // Then we want X, such that 1.01 ^ X = 45 * 1000 / 200. Some quick math shows
  27 // that X = 544.
  28 const int kHistogramBucketCount = 544;
  29
  30 }  // namespace
  31
  32 scoped_ptr<FirstWebContentsProfiler>
  33 FirstWebContentsProfiler::CreateProfilerForFirstWebContents(
  34     Delegate* delegate) {
  35   DCHECK(delegate);
  36   for (chrome::BrowserIterator iterator; !iterator.done(); iterator.Next()) {
  37     Browser* browser = *iterator;
  38     content::WebContents* web_contents =
  39         browser->tab_strip_model()->GetActiveWebContents();
  40     if (web_contents) {
  41       return scoped_ptr<FirstWebContentsProfiler>(
  42           new FirstWebContentsProfiler(web_contents, delegate));
  43     }
  44   }
  45   return nullptr;
  46 }
  47
  48 bool FirstWebContentsProfiler::ShouldCollectMetrics() {
  49   chrome::VersionInfo::Channel channel = chrome::VersionInfo::GetChannel();
  50   return channel == chrome::VersionInfo::CHANNEL_CANARY ||
  51          channel == chrome::VersionInfo::CHANNEL_DEV;
  52 }
  53
  54 FirstWebContentsProfiler::FirstWebContentsProfiler(
  55     content::WebContents* web_contents,
  56     Delegate* delegate)
  57     : content::WebContentsObserver(web_contents),
  58       collected_paint_metric_(false),
  59       collected_load_metric_(false),
  60       delegate_(delegate) {
  61   process_creation_time_ = base::CurrentProcessInfo::CreationTime();
  62 }
  63
  64 void FirstWebContentsProfiler::DidFirstVisuallyNonEmptyPaint() {
  65   if (collected_paint_metric_)
  66     return;
  67
  68   collected_paint_metric_ = true;
  69   if (!process_creation_time_.is_null()) {
  70     base::TimeDelta elapsed = base::Time::Now() - process_creation_time_;
  71
  72     // TODO(erikchen): Revisit these metrics once data has been collected to
  73     // determine whether using more buckets reduces noise and provides higher
  74     // quality information.
  75     UMA_HISTOGRAM_CUSTOM_TIMES(
  76         "Startup.Experimental.FirstWebContents.NonEmptyPaint."
  77         "ManyBuckets",
  78         elapsed,
  79         base::TimeDelta::FromMilliseconds(kHistogramMinTimeMilliseconds),
  80         base::TimeDelta::FromSeconds(kHistogramMaxTimeSeconds),
  81         kHistogramBucketCount);
  82     UMA_HISTOGRAM_LONG_TIMES_100(
  83         "Startup.Experimental.FirstWebContents.NonEmptyPaint.StandardBuckets",
  84         elapsed);
  85   }
  86
  87   if (IsFinishedCollectingMetrics())
  88     FinishedCollectingMetrics();
  89 }
  90
  91 void FirstWebContentsProfiler::DocumentOnLoadCompletedInMainFrame() {
  92   if (collected_load_metric_)
  93     return;
  94
  95   collected_load_metric_ = true;
  96   if (!process_creation_time_.is_null()) {
  97     base::TimeDelta elapsed = base::Time::Now() - process_creation_time_;
  98
  99     // TODO(erikchen): Revisit these metrics once data has been collected to
 100     // determine whether using more buckets reduces noise and provides higher
 101     // quality information.
 102     UMA_HISTOGRAM_CUSTOM_TIMES(
 103         "Startup.Experimental.FirstWebContents.MainFrameLoad."
 104         "ManyBuckets",
 105         elapsed,
 106         base::TimeDelta::FromMilliseconds(kHistogramMinTimeMilliseconds),
 107         base::TimeDelta::FromSeconds(kHistogramMaxTimeSeconds),
 108         kHistogramBucketCount);
 109     UMA_HISTOGRAM_LONG_TIMES_100(
 110         "Startup.Experimental.FirstWebContents.MainFrameLoad.StandardBuckets",
 111         elapsed);
 112   }
 113
 114   if (IsFinishedCollectingMetrics())
 115     FinishedCollectingMetrics();
 116 }
 117
 118 void FirstWebContentsProfiler::WebContentsDestroyed() {
 119   FinishedCollectingMetrics();
 120 }
 121
 122 bool FirstWebContentsProfiler::IsFinishedCollectingMetrics() {
 123   return collected_paint_metric_ && collected_load_metric_;
 124 }
 125
 126 void FirstWebContentsProfiler::FinishedCollectingMetrics() {
 127   delegate_->ProfilerFinishedCollectingMetrics();
 128 }
 129
 130 #endif  // !defined(OS_ANDROID)