chrome/browser/prerender/prerender_histograms.h

   1 // Copyright (c) 2012 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 #ifndef CHROME_BROWSER_PRERENDER_PRERENDER_HISTOGRAMS_H_
   6 #define CHROME_BROWSER_PRERENDER_PRERENDER_HISTOGRAMS_H_
   7
   8 #include <string>
   9
  10 #include "base/time/time.h"
  11 #include "chrome/browser/prerender/prerender_contents.h"
  12 #include "chrome/browser/prerender/prerender_events.h"
  13 #include "chrome/browser/prerender/prerender_final_status.h"
  14 #include "chrome/browser/prerender/prerender_local_predictor.h"
  15 #include "chrome/browser/prerender/prerender_origin.h"
  16 #include "url/gurl.h"
  17
  18 namespace prerender {
  19
  20 // Navigation type for histograms.
  21 enum NavigationType {
  22   // A normal completed navigation.
  23   NAVIGATION_TYPE_NORMAL,
  24   // A completed navigation or swap that began as a prerender.
  25   NAVIGATION_TYPE_PRERENDERED,
  26   // A normal completed navigation in the control group or with a control
  27   // prerender that would have been prerendered.
  28   NAVIGATION_TYPE_WOULD_HAVE_BEEN_PRERENDERED,
  29   NAVIGATION_TYPE_MAX,
  30 };
  31
  32 // PrerenderHistograms is responsible for recording all prerender specific
  33 // histograms for PrerenderManager.  It keeps track of the type of prerender
  34 // currently underway (based on the PrerenderOrigin of the most recent
  35 // prerenders, and any experiments detected).
  36 // PrerenderHistograms does not necessarily record all histograms related to
  37 // prerendering, only the ones in the context of PrerenderManager.
  38 class PrerenderHistograms {
  39  public:
  40   // Owned by a PrerenderManager object for the lifetime of the
  41   // PrerenderManager.
  42   PrerenderHistograms();
  43
  44   // Records the perceived page load time for a page - effectively the time from
  45   // when the user navigates to a page to when it finishes loading.  The actual
  46   // load may have started prior to navigation due to prerender hints.
  47   void RecordPerceivedPageLoadTime(Origin origin,
  48                                    base::TimeDelta perceived_page_load_time,
  49                                    NavigationType navigation_type,
  50                                    const GURL& url);
  51
  52   // Records, in a histogram, the percentage of the page load time that had
  53   // elapsed by the time it is swapped in.  Values outside of [0, 1.0] are
  54   // invalid and ignored.
  55   void RecordPercentLoadDoneAtSwapin(Origin origin, double fraction) const;
  56
  57   // Records the actual pageload time of a prerender that has not been swapped
  58   // in yet, but finished loading.
  59   void RecordPageLoadTimeNotSwappedIn(Origin origin,
  60                                       base::TimeDelta page_load_time,
  61                                       const GURL& url) const;
  62
  63   // Records the time from when a page starts prerendering to when the user
  64   // navigates to it. This must be called on the UI thread.
  65   void RecordTimeUntilUsed(Origin origin,
  66                            base::TimeDelta time_until_used) const;
  67
  68   // Record a PerSessionCount data point.
  69   void RecordPerSessionCount(Origin origin, int count) const;
  70
  71   // Record time between two prerender requests.
  72   void RecordTimeBetweenPrerenderRequests(Origin origin,
  73                                           base::TimeDelta time) const;
  74
  75   // Record a final status of a prerendered page in a histogram.
  76   void RecordFinalStatus(Origin origin,
  77                          uint8 experiment_id,
  78                          PrerenderContents::MatchCompleteStatus mc_status,
  79                          FinalStatus final_status) const;
  80
  81   // To be called when a new prerender is added.
  82   void RecordPrerender(Origin origin, const GURL& url);
  83
  84   // To be called when a new prerender is started.
  85   void RecordPrerenderStarted(Origin origin) const;
  86
  87   // To be called when we know how many prerenders are running after starting
  88   // a prerender.
  89   void RecordConcurrency(size_t prerender_count) const;
  90
  91   // Called when we swap in a prerender.
  92   void RecordUsedPrerender(Origin origin) const;
  93
  94   // Record the time since a page was recently visited.
  95   void RecordTimeSinceLastRecentVisit(Origin origin,
  96                                       base::TimeDelta time) const;
  97
  98   // Records a prerender event.
  99   void RecordEvent(Origin origin, uint8 experiment_id, PrerenderEvent event)
 100       const;
 101
 102   // Record a prerender cookie status bitmap. Must be in the range
 103   // [0, PrerenderContents::kNumCookieStatuses).
 104   void RecordCookieStatus(Origin origin,
 105                           uint8 experiment_id,
 106                           int cookie_status) const;
 107
 108   void RecordPrerenderPageVisitedStatus(Origin origin,
 109                                         uint8 experiment_id,
 110                                         bool visited_before) const;
 111
 112   // Record the bytes in the prerender, whether it was used or not, and the
 113   // total number of bytes fetched for this profile since the last call to
 114   // RecordBytes.
 115   void RecordNetworkBytes(bool used,
 116                           int64 prerender_bytes,
 117                           int64 profile_bytes);
 118
 119  private:
 120   base::TimeTicks GetCurrentTimeTicks() const;
 121
 122   // Returns the time elapsed since the last prerender happened.
 123   base::TimeDelta GetTimeSinceLastPrerender() const;
 124
 125   // Returns whether the PrerenderManager is currently within the prerender
 126   // window - effectively, up to 30 seconds after a prerender tag has been
 127   // observed.
 128   bool WithinWindow() const;
 129
 130   // Returns the current experiment.
 131   uint8 GetCurrentExperimentId() const;
 132
 133   // Returns whether or not there is currently an origin/experiment wash.
 134   bool IsOriginExperimentWash() const;
 135
 136   // An integer indicating a Prerendering Experiment being currently conducted.
 137   // (The last experiment ID seen).
 138   uint8 last_experiment_id_;
 139
 140   // Origin of the last prerender seen.
 141   Origin last_origin_;
 142
 143   // A boolean indicating that we have recently encountered a combination of
 144   // different experiments and origins, making an attribution of PPLT's to
 145   // experiments / origins impossible.
 146   bool origin_experiment_wash_;
 147
 148   // The time when we last saw a prerender request coming from a renderer.
 149   // This is used to record perceived PLT's for a certain amount of time
 150   // from the point that we last saw a <link rel=prerender> tag.
 151   base::TimeTicks last_prerender_seen_time_;
 152
 153   // Indicates whether we have recorded page load events after the most
 154   // recent prerender.  These must be initialized to true, so that we don't
 155   // start recording events before the first prerender occurs.
 156   bool seen_any_pageload_;
 157   bool seen_pageload_started_after_prerender_;
 158
 159   DISALLOW_COPY_AND_ASSIGN(PrerenderHistograms);
 160 };
 161
 162 }  // namespace prerender
 163
 164 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_HISTOGRAMS_H_