components/scheduling_metrics/thread_metrics.cc

   1 // Copyright 2018 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "components/scheduling_metrics/thread_metrics.h"
   6
   7 namespace scheduling_metrics {
   8
   9 namespace {
  10
  11 // Threshold for discarding ultra-long tasks. It is assumed that ultra-long
  12 // tasks are reporting glitches (e.g. system falling asleep on the middle of the
  13 // task).
  14 constexpr base::TimeDelta kLongTaskDiscardingThreshold =
  15     base::TimeDelta::FromSeconds(30);
  16
  17 }  // namespace
  18
  19 ThreadMetrics::ThreadMetrics(ThreadType thread_type,
  20                              bool has_cpu_timing_for_each_task)
  21     : thread_type_(thread_type),
  22       has_cpu_timing_for_each_task_(has_cpu_timing_for_each_task),
  23       last_known_time_(has_cpu_timing_for_each_task_ ? base::ThreadTicks::Now()
  24                                                      : base::ThreadTicks()),
  25       thread_task_duration_reporter_(
  26           "Scheduler.Experimental.WallTimePerThread"),
  27       thread_task_cpu_duration_reporter_(
  28           "Scheduler.Experimental.CPUTimePerThread"),
  29       tracked_cpu_duration_reporter_(
  30           "Scheduler.Experimental.CPUTimePerThread.Tracked"),
  31       non_tracked_cpu_duration_reporter_(
  32           "Scheduler.Experimental.CPUTimePerThread.Untracked") {}
  33
  34 ThreadMetrics::~ThreadMetrics() {}
  35
  36 bool ThreadMetrics::ShouldDiscardTask(
  37     base::sequence_manager::TaskQueue* queue,
  38     const base::sequence_manager::Task& task,
  39     const base::sequence_manager::TaskQueue::TaskTiming& task_timing) {
  40   // TODO(altimin): Investigate the relationship between thread time and
  41   // wall time for discarded tasks.
  42   return task_timing.wall_duration() > kLongTaskDiscardingThreshold;
  43 }
  44
  45 void ThreadMetrics::RecordTaskMetrics(
  46     base::sequence_manager::TaskQueue* queue,
  47     const base::sequence_manager::Task& task,
  48     const base::sequence_manager::TaskQueue::TaskTiming& task_timing) {
  49   DCHECK(!has_cpu_timing_for_each_task_ || task_timing.has_thread_time());
  50   thread_task_duration_reporter_.RecordTask(thread_type_,
  51                                             task_timing.wall_duration());
  52
  53   if (!task_timing.has_thread_time())
  54     return;
  55   thread_task_cpu_duration_reporter_.RecordTask(thread_type_,
  56                                                 task_timing.thread_duration());
  57   if (has_cpu_timing_for_each_task_) {
  58     non_tracked_cpu_duration_reporter_.RecordTask(
  59         thread_type_, task_timing.start_thread_time() - last_known_time_);
  60     tracked_cpu_duration_reporter_.RecordTask(thread_type_,
  61                                               task_timing.thread_duration());
  62
  63     last_known_time_ = task_timing.end_thread_time();
  64   }
  65 }
  66
  67 }  // namespace scheduling_metrics