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base / memory / memory_pressure_monitor.h [blame]
// Copyright 2015 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef BASE_MEMORY_MEMORY_PRESSURE_MONITOR_H_
#define BASE_MEMORY_MEMORY_PRESSURE_MONITOR_H_
#include "base/base_export.h"
#include "base/functional/callback.h"
#include "base/memory/memory_pressure_listener.h"
#include "base/time/time.h"
namespace base {
// TODO(chrisha): Make this a concrete class with per-OS implementations rather
// than an abstract base class.
// Declares the interface for a MemoryPressureMonitor. There are multiple
// OS specific implementations of this class. An instance of the memory
// pressure observer is created at the process level, tracks memory usage, and
// pushes memory state change notifications to the static function
// base::MemoryPressureListener::NotifyMemoryPressure. This is turn notifies
// all MemoryPressureListener instances via a callback.
class BASE_EXPORT MemoryPressureMonitor {
public:
using MemoryPressureLevel = base::MemoryPressureListener::MemoryPressureLevel;
using DispatchCallback =
base::RepeatingCallback<void(MemoryPressureLevel level)>;
MemoryPressureMonitor(const MemoryPressureMonitor&) = delete;
MemoryPressureMonitor& operator=(const MemoryPressureMonitor&) = delete;
virtual ~MemoryPressureMonitor();
// Return the singleton MemoryPressureMonitor.
static MemoryPressureMonitor* Get();
// Returns the currently observed memory pressure.
virtual MemoryPressureLevel GetCurrentPressureLevel() const = 0;
protected:
MemoryPressureMonitor();
};
} // namespace base
#endif // BASE_MEMORY_MEMORY_PRESSURE_MONITOR_H_