Add out of memory stats for graphics memory, discards per minute

chrome/browser/chromeos/memory/oom_priority_manager.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_CHROMEOS_MEMORY_OOM_PRIORITY_MANAGER_H_
 #define CHROME_BROWSER_CHROMEOS_MEMORY_OOM_PRIORITY_MANAGER_H_
 
 #include <vector>
 
 #include "base/compiler_specific.h"
@@ skipping 24 matching lines @@
 // The algorithm used favors killing tabs that are not selected, not pinned,
 // and have been idle for longest, in that order of priority.
 class OomPriorityManager : public content::NotificationObserver {
  public:
   OomPriorityManager();
   virtual ~OomPriorityManager();
 
   // Number of discard events since Chrome started.
   int discard_count() const { return discard_count_; }
 
+  // See member comment.
+  bool recent_tab_discard() const { return recent_tab_discard_; }
+
   void Start();
   void Stop();
 
   // Returns list of tab titles sorted from most interesting (don't kill)
   // to least interesting (OK to kill).
   std::vector<string16> GetTabTitles();
 
   // Discards a tab to free the memory occupied by its renderer.
   // Tab still exists in the tab-strip; clicking on it will reload it.
   // Returns true if it successfully found a tab and discarded it.
@@ skipping 29 matching lines @@
   static bool IsReloadableUI(const GURL& url);
 
   // Discards a tab with the given unique ID.  Returns true if discard occurred.
   bool DiscardTabById(int64 target_web_contents_id);
 
   // Records UMA histogram statistics for a tab discard. We record statistics
   // for user triggered discards via chrome://discards/ because that allows us
   // to manually test the system.
   void RecordDiscardStatistics();
 
+  // Record whether we ran out of memory during a recent time interval.
+  // This allows us to normalize low memory statistics versus usage.
+  void RecordRecentTabDiscard();
+
   // Purges data structures in the browser that can be easily recomputed.
   void PurgeBrowserMemory();
 
   // Returns the number of tabs open in all browser instances.
   int GetTabCount() const;
 
   TabStatsList GetTabStatsOnUIThread();
 
   // Called when the timer fires, sets oom_adjust_score for all renderers.
   void AdjustOomPriorities();
 
   // Called by AdjustOomPriorities.
   void AdjustOomPrioritiesOnFileThread(TabStatsList stats_list);
 
   // Posts AdjustFocusedTabScore task to the file thread.
   void OnFocusTabScoreAdjustmentTimeout();
 
   // Sets the score of the focused tab to the least value.
   void AdjustFocusedTabScoreOnFileThread();
 
   static bool CompareTabStats(TabStats first, TabStats second);
 
   virtual void Observe(int type,
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) OVERRIDE;
 
   base::RepeatingTimer<OomPriorityManager> timer_;
   base::OneShotTimer<OomPriorityManager> focus_tab_score_adjust_timer_;
+  base::RepeatingTimer<OomPriorityManager> recent_tab_discard_timer_;
   content::NotificationRegistrar registrar_;
 
   // This lock is for pid_to_oom_score_ and focus_tab_pid_.
   base::Lock pid_to_oom_score_lock_;
   // map maintaining the process - oom_score mapping.
   typedef base::hash_map<base::ProcessHandle, int> ProcessScoreMap;
   ProcessScoreMap pid_to_oom_score_;
   base::ProcessHandle focused_tab_pid_;
 
   // Observer for the kernel low memory signal.  NULL if tab discarding is
   // disabled.
   scoped_ptr<LowMemoryObserver> low_memory_observer_;
 
   // Wall-clock time when the priority manager started running.
   base::TimeTicks start_time_;
 
   // Wall-clock time of last tab discard during this browsing session, or 0 if
   // no discard has happened yet.
   base::TimeTicks last_discard_time_;
 
   // Wall-clock time of last priority adjustment, used to correct the above
   // times for discontinuities caused by suspend/resume.
   base::TimeTicks last_adjust_time_;
 
   // Number of times we have discarded a tab, for statistics.
   int discard_count_;
 
+  // Whether a tab discard event has occurred during the last time interval,
+  // used for statistics normalized by usage.
+  bool recent_tab_discard_;
+
   DISALLOW_COPY_AND_ASSIGN(OomPriorityManager);
 };
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_CHROMEOS_MEMORY_OOM_PRIORITY_MANAGER_H_