Index: components/scheduler/base/queueing_time_estimator.cc |
diff --git a/components/scheduler/base/queueing_time_estimator.cc b/components/scheduler/base/queueing_time_estimator.cc |
deleted file mode 100644 |
index 1402380f5721e24ceb34ae9b87ca5785ed565760..0000000000000000000000000000000000000000 |
--- a/components/scheduler/base/queueing_time_estimator.cc |
+++ /dev/null |
@@ -1,87 +0,0 @@ |
-// Copyright 2016 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/base/queueing_time_estimator.h" |
- |
-#include "base/time/default_tick_clock.h" |
- |
-namespace scheduler { |
- |
-namespace { |
- |
-// This method computes the expected queueing time of a randomly distributed |
-// task R within a window containing a single task T. Let T' be the time range |
-// for which T overlaps the window. We first compute the probability that R will |
-// start within T'. We then compute the expected queueing duration if R does |
-// start within this range. Since the start time of R is uniformly distributed |
-// within the window, this is equal to the average of the queueing times if R |
-// started at the beginning or end of T'. The expected queueing time of T is the |
-// probability that R will start within T', multiplied by the expected queueing |
-// duration if R does fall in this range. |
-base::TimeDelta ExpectedQueueingTimeFromTask(base::TimeTicks task_start, |
- base::TimeTicks task_end, |
- base::TimeTicks window_start, |
- base::TimeTicks window_end) { |
- DCHECK(task_start <= task_end); |
- DCHECK(task_start <= window_end); |
- DCHECK(window_start < window_end); |
- DCHECK(task_end >= window_start); |
- base::TimeTicks task_in_window_start_time = |
- std::max(task_start, window_start); |
- base::TimeTicks task_in_window_end_time = |
- std::min(task_end, window_end); |
- DCHECK(task_in_window_end_time <= task_in_window_end_time); |
- |
- double probability_of_this_task = |
- static_cast<double>((task_in_window_end_time - task_in_window_start_time) |
- .InMicroseconds()) / |
- (window_end - window_start).InMicroseconds(); |
- |
- base::TimeDelta expected_queueing_duration_within_task = |
- ((task_end - task_in_window_start_time) + |
- (task_end - task_in_window_end_time)) / |
- 2; |
- |
- return base::TimeDelta::FromMillisecondsD( |
- probability_of_this_task * |
- expected_queueing_duration_within_task.InMillisecondsF()); |
-} |
- |
-} // namespace |
- |
-QueueingTimeEstimator::QueueingTimeEstimator( |
- QueueingTimeEstimator::Client* client, |
- base::TimeDelta window_duration) |
- : client_(client), |
- window_duration_(window_duration), |
- window_start_time_() {} |
- |
-void QueueingTimeEstimator::OnToplevelTaskCompleted( |
- base::TimeTicks task_start_time, |
- base::TimeTicks task_end_time) { |
- if (window_start_time_.is_null()) |
- window_start_time_ = task_start_time; |
- |
- while (TimePastWindowEnd(task_end_time)) { |
- if (!TimePastWindowEnd(task_start_time)) { |
- // Include the current task in this window. |
- current_expected_queueing_time_ += ExpectedQueueingTimeFromTask( |
- task_start_time, task_end_time, window_start_time_, |
- window_start_time_ + window_duration_); |
- } |
- client_->OnQueueingTimeForWindowEstimated(current_expected_queueing_time_); |
- window_start_time_ += window_duration_; |
- current_expected_queueing_time_ = base::TimeDelta(); |
- } |
- |
- current_expected_queueing_time_ += ExpectedQueueingTimeFromTask( |
- task_start_time, task_end_time, window_start_time_, |
- window_start_time_ + window_duration_); |
-} |
- |
-bool QueueingTimeEstimator::TimePastWindowEnd(base::TimeTicks time) { |
- return time > window_start_time_ + window_duration_; |
-} |
- |
-} // namespace scheduler |