1 // Copyright (c) 2010 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_OOM_PRIORITY_MANAGER_H_ 6 #define CHROME_BROWSER_OOM_PRIORITY_MANAGER_H_ 7 8 #include <list> 9 10 #include "base/timer.h" 11 #include "base/process.h" 12 13 namespace browser { 14 15 // The OomPriorityManager periodically checks (see 16 // ADJUSTMENT_INTERVAL_SECONDS in the source) the status of renderers 17 // and adjusts the out of memory (OOM) adjustment value (in 18 // /proc/<pid>/oom_adj) of the renderers so that they match the 19 // algorithm embedded here for priority in being killed upon OOM 20 // conditions. 21 // 22 // The algorithm used favors killing tabs that are not pinned, have 23 // been idle for longest, and take up the most memory, in that order 24 // of priority. We round the idle times to the nearest few minutes 25 // (see BUCKET_INTERVAL_MINUTES in the source) so that we can bucket 26 // them, as no two tabs will have exactly the same idle time. 27 class OomPriorityManager { 28 public: 29 OomPriorityManager(); 30 ~OomPriorityManager(); 31 32 private: 33 struct RendererStats { 34 bool is_pinned; 35 base::TimeTicks last_selected; 36 size_t memory_used; 37 base::ProcessHandle renderer_handle; 38 }; 39 typedef std::list<RendererStats> StatsList; 40 41 void StartTimer(); 42 void StopTimer(); 43 44 // Posts DoAdjustOomPriorities task to the file thread. Called when 45 // the timer fires. 46 void AdjustOomPriorities(); 47 48 // Called by AdjustOomPriorities. Runs on the file thread. 49 void DoAdjustOomPriorities(StatsList list); 50 51 static bool CompareRendererStats(RendererStats first, RendererStats second); 52 53 base::RepeatingTimer<OomPriorityManager> timer_; 54 55 DISALLOW_COPY_AND_ASSIGN(OomPriorityManager); 56 }; 57 } // namespace browser 58 59 DISABLE_RUNNABLE_METHOD_REFCOUNT(browser::OomPriorityManager); 60 61 #endif // CHROME_BROWSER_OOM_PRIORITY_MANAGER_H_ 62
