| // 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_SCHEDULER_RENDERER_TASK_COST_ESTIMATOR_H_ |
| #define COMPONENTS_SCHEDULER_RENDERER_TASK_COST_ESTIMATOR_H_ |
| |
| #include "base/message_loop/message_loop.h" |
| #include "base/time/time.h" |
| #include "cc/base/rolling_time_delta_history.h" |
| #include "components/scheduler/scheduler_export.h" |
| |
| namespace scheduler { |
| |
| // Estimates the cost of running tasks based on historical timing data. |
| class SCHEDULER_EXPORT TaskCostEstimator |
| : public base::MessageLoop::TaskObserver { |
| public: |
| TaskCostEstimator(int sample_count, double estimation_percentile); |
| ~TaskCostEstimator() override; |
| |
| base::TimeDelta expected_task_duration() const { |
| return expected_task_duration_; |
| } |
| |
| // TaskObserver implementation: |
| void WillProcessTask(const base::PendingTask& pending_task) override; |
| void DidProcessTask(const base::PendingTask& pending_task) override; |
| |
| void Clear(); |
| |
| protected: |
| // Virtual for testing. |
| virtual base::TimeTicks Now(); |
| |
| private: |
| cc::RollingTimeDeltaHistory rolling_time_delta_history_; |
| int outstanding_task_count_; |
| double estimation_percentile_; |
| base::TimeTicks task_start_time_; |
| base::TimeDelta expected_task_duration_; |
| |
| DISALLOW_COPY_AND_ASSIGN(TaskCostEstimator); |
| }; |
| |
| } // namespace scheduler |
| |
| #endif // COMPONENTS_SCHEDULER_RENDERER_TASK_COST_ESTIMATOR_H_ |