| // 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. |
| |
| #include "components/scheduler/renderer/task_cost_estimator.h" |
| |
| #include "base/time/default_tick_clock.h" |
| |
| namespace scheduler { |
| |
| TaskCostEstimator::TaskCostEstimator(base::TickClock* time_source, |
| int sample_count, |
| double estimation_percentile) |
| : rolling_time_delta_history_(sample_count), |
| time_source_(time_source), |
| outstanding_task_count_(0), |
| estimation_percentile_(estimation_percentile) {} |
| |
| TaskCostEstimator::~TaskCostEstimator() {} |
| |
| void TaskCostEstimator::WillProcessTask(const base::PendingTask& pending_task) { |
| // Avoid measuring the duration in nested run loops. |
| if (++outstanding_task_count_ == 1) |
| task_start_time_ = time_source_->NowTicks(); |
| } |
| |
| void TaskCostEstimator::DidProcessTask(const base::PendingTask& pending_task) { |
| if (--outstanding_task_count_ == 0) { |
| base::TimeDelta duration = time_source_->NowTicks() - task_start_time_; |
| rolling_time_delta_history_.InsertSample(duration); |
| } |
| } |
| |
| base::TimeDelta TaskCostEstimator::expected_task_duration() const { |
| return rolling_time_delta_history_.Percentile(estimation_percentile_); |
| } |
| |
| void TaskCostEstimator::Clear() { |
| rolling_time_delta_history_.Clear(); |
| expected_task_duration_ = base::TimeDelta(); |
| } |
| |
| } // namespace scheduler |