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