| // Copyright 2015 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 COMPONENTS_MEMORY_PRESSURE_MEMORY_PRESSURE_STATS_COLLECTOR_H_ |
| #define COMPONENTS_MEMORY_PRESSURE_MEMORY_PRESSURE_STATS_COLLECTOR_H_ |
| |
| #include "base/time/time.h" |
| #include "components/memory_pressure/memory_pressure_listener.h" |
| |
| namespace base { |
| class TickClock; |
| } |
| |
| namespace memory_pressure { |
| |
| // Enumeration of UMA memory pressure levels. The pressure level enum defined in |
| // MemoryPressureListener is non-contiguous. This enum is a contiguous version |
| // of that for use with UMA. Both it and histograms.xml must be kept in sync |
| // with the MemoryPressureListener enum. Included in the header so that |
| // UMA_MEMORY_PRESSURE_LEVEL_COUNT is available. |
| enum MemoryPressureLevelUMA { |
| UMA_MEMORY_PRESSURE_LEVEL_NONE = 0, |
| UMA_MEMORY_PRESSURE_LEVEL_MODERATE = 1, |
| UMA_MEMORY_PRESSURE_LEVEL_CRITICAL = 2, |
| // This must be the last value in the enum. |
| UMA_MEMORY_PRESSURE_LEVEL_COUNT, |
| }; |
| |
| // Enumeration of UMA pressure level changes. This needs to be kept in sync |
| // with histograms.xml and the memory pressure levels defined in |
| // MemoryPressureListener. Exposed for unittesting. |
| enum MemoryPressureLevelChangeUMA { |
| UMA_MEMORY_PRESSURE_LEVEL_CHANGE_NONE_TO_MODERATE = 0, |
| UMA_MEMORY_PRESSURE_LEVEL_CHANGE_NONE_TO_CRITICAL = 1, |
| UMA_MEMORY_PRESSURE_LEVEL_CHANGE_MODERATE_TO_CRITICAL = 2, |
| UMA_MEMORY_PRESSURE_LEVEL_CHANGE_CRITICAL_TO_MODERATE = 3, |
| UMA_MEMORY_PRESSURE_LEVEL_CHANGE_CRITICAL_TO_NONE = 4, |
| UMA_MEMORY_PRESSURE_LEVEL_CHANGE_MODERATE_TO_NONE = 5, |
| // This must be the last value in the enum. |
| UMA_MEMORY_PRESSURE_LEVEL_CHANGE_COUNT |
| }; |
| |
| // Class that is responsible for collecting and eventually reporting memory |
| // pressure statistics. Contributes to the "Memory.PressureLevel" and |
| // "Memory.PressureLevelChanges" histograms. |
| // |
| // On platforms with a polling memory pressure implementation the |
| // UpdateStatistics function will be invoked every time the pressure is polled. |
| // On non-polling platforms (Mac, Android) it will be invoked on a periodic |
| // timer, and at the moment of pressure level changes. |
| class MemoryPressureStatsCollector { |
| public: |
| using MemoryPressureLevel = MemoryPressureListener::MemoryPressureLevel; |
| |
| // The provided |tick_clock| must outlive this class. |
| MemoryPressureStatsCollector(base::TickClock* tick_clock); |
| |
| // This is to be called periodically to ensure that up to date statistics |
| // have been reported. |
| void UpdateStatistics(MemoryPressureLevel current_pressure_level); |
| |
| private: |
| friend class TestMemoryPressureStatsCollector; |
| |
| // Helper functions for delivering collected statistics. |
| static void ReportCumulativeTime(MemoryPressureLevel pressure_level, |
| int seconds); |
| static void ReportLevelChange(MemoryPressureLevel old_pressure_level, |
| MemoryPressureLevel new_pressure_level); |
| |
| // The tick clock in use. This class is intended to be owned by a class with |
| // a tick clock, and ownership remains there. Also intended as a test seam. |
| base::TickClock* tick_clock_; |
| |
| // Buckets of time that have been spent in different pressure levels, but |
| // not yet reported. At every call to UpdateStatistics these buckets will be |
| // drained of as many 'full' seconds of time as possible and reported via |
| // UMA. The remaining time (< 1000 ms) will be left in the bucket to be rolled |
| // into a later UMA report. |
| base::TimeDelta unreported_cumulative_time_[UMA_MEMORY_PRESSURE_LEVEL_COUNT]; |
| |
| // The last observed pressure level and the time at which it was observed, and |
| // the time when this pressure level started. |
| MemoryPressureLevel last_pressure_level_; |
| base::TimeTicks last_update_time_; |
| |
| DISALLOW_COPY_AND_ASSIGN(MemoryPressureStatsCollector); |
| }; |
| |
| } // namespace memory_pressure |
| |
| #endif // COMPONENTS_MEMORY_PRESSURE_MEMORY_PRESSURE_STATS_COLLECTOR_H_ |