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