compositor_timing_history.cc

// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "cc/metrics/compositor_timing_history.h"

#include <stddef.h>
#include <stdint.h>

#include <algorithm>
#include <utility>
#include <vector>

#include "base/memory/ptr_util.h"
#include "base/metrics/field_trial_params.h"
#include "base/metrics/histogram_macros.h"
#include "base/notreached.h"
#include "base/trace_event/trace_event.h"
#include "cc/base/features.h"
#include "cc/debug/rendering_stats_instrumentation.h"

namespace cc {

class CompositorTimingHistory::UMAReporter {
 public:
  virtual ~UMAReporter() = default;

  // Throughput measurements
  virtual void AddDrawInterval(base::TimeDelta interval) = 0;

  // Latency measurements
  virtual void AddBeginImplFrameLatency(base::TimeDelta delta) = 0;
  virtual void AddDrawDuration(base::TimeDelta duration) = 0;

  // crbug.com/758439: the following functions are used to report timing in
  // certain conditions targeting blink / compositor animations.
  // Only the renderer would get the meaningful data.
  virtual void AddDrawIntervalWithCustomPropertyAnimations(
      base::TimeDelta duration) = 0;

  virtual void AddImplFrameDeadlineType(
      CompositorTimingHistory::DeadlineMode deadline_mode) = 0;
};

namespace {

// Used to generate a unique id when emitting the "Long Draw Interval" trace
// event.
int g_num_long_draw_intervals = 0;

// The threshold to emit a trace event is the 99th percentile
// of the histogram on Windows Stable as of Feb 26th, 2020.
constexpr base::TimeDelta kDrawIntervalTraceThreshold =
    base::Microseconds(34478);

// Using the 90th percentile will disable latency recovery
// if we are missing the deadline approximately ~6 times per
// second.
// TODO(brianderson): Fine tune the percentiles below.
const size_t kDurationHistorySize = 60;
const double kBeginMainFrameQueueDurationEstimationPercentile = 90.0;
const double kBeginMainFrameQueueDurationCriticalEstimationPercentile = 90.0;
const double kBeginMainFrameQueueDurationNotCriticalEstimationPercentile = 90.0;
const double kBeginMainFrameStartToReadyToCommitEstimationPercentile = 90.0;
const double kCommitEstimatePercentile = 90.0;
const double kCommitToReadyToActivateEstimationPercentile = 90.0;
const double kPrepareTilesEstimationPercentile = 90.0;
const double kActivateEstimationPercentile = 90.0;
const double kDrawEstimationPercentile = 90.0;

double BeginMainFrameStartToReadyToCommitCriticalPercentile() {
  if (base::FeatureList::IsEnabled(
          features::kDurationEstimatesInCompositorTimingHistory)) {
    double result = base::GetFieldTrialParamByFeatureAsDouble(
        features::kDurationEstimatesInCompositorTimingHistory,
        "BMFStartCritialPercentile", -1.0);
    if (result > 0)
      return result;
  }
  return 90.0;
}

double BeginMainFrameStartToReadyToCommitNonCriticalPercentile() {
  if (base::FeatureList::IsEnabled(
          features::kDurationEstimatesInCompositorTimingHistory)) {
    double result = base::GetFieldTrialParamByFeatureAsDouble(
        features::kDurationEstimatesInCompositorTimingHistory,
        "BMFStartNonCritialPercentile", -1.0);
    if (result > 0)
      return result;
  }
  return 90.0;
}

double BeginMainFrameQueueToActivateCriticalPercentile() {
  if (base::FeatureList::IsEnabled(
          features::kDurationEstimatesInCompositorTimingHistory)) {
    double result = base::GetFieldTrialParamByFeatureAsDouble(
        features::kDurationEstimatesInCompositorTimingHistory,
        "BMFQueueCritialPercentile", -1.0);
    if (result > 0)
      return result;
  }
  return 90.0;
}

// This macro is deprecated since its bucket count uses too much bandwidth.
// It also has sub-optimal range and bucket distribution.
// TODO(brianderson): Delete this macro and associated UMAs once there is
// sufficient overlap with the re-bucketed UMAs.
#define UMA_HISTOGRAM_CUSTOM_TIMES_MICROS(name, sample)                     \
  UMA_HISTOGRAM_CUSTOM_COUNTS(name, sample.InMicroseconds(),                \
                              kUmaDurationMinMicros, kUmaDurationMaxMicros, \
                              kUmaDurationBucketCount);

// ~90 VSync aligned UMA buckets.
const int kUMAVSyncBuckets[] = {
    // Powers of two from 0 to 2048 us @ 50% precision
    1,
    2,
    4,
    8,
    16,
    32,
    64,
    128,
    256,
    512,
    1024,
    2048,
    // Every 8 Hz from 256 Hz to 128 Hz @ 3-6% precision
    3906,
    4032,
    4167,
    4310,
    4464,
    4630,
    4808,
    5000,
    5208,
    5435,
    5682,
    5952,
    6250,
    6579,
    6944,
    7353,
    // Every 4 Hz from 128 Hz to 64 Hz @ 3-6% precision
    7813,
    8065,
    8333,
    8621,
    8929,
    9259,
    9615,
    10000,
    10417,
    10870,
    11364,
    11905,
    12500,
    13158,
    13889,
    14706,
    // Every 2 Hz from 64 Hz to 32 Hz @ 3-6% precision
    15625,
    16129,
    16667,
    17241,
    17857,
    18519,
    19231,
    20000,
    20833,
    21739,
    22727,
    23810,
    25000,
    26316,
    27778,
    29412,
    // Every 1 Hz from 32 Hz to 1 Hz @ 3-33% precision
    31250,
    32258,
    33333,
    34483,
    35714,
    37037,
    38462,
    40000,
    41667,
    43478,
    45455,
    47619,
    50000,
    52632,
    55556,
    58824,
    62500,
    66667,
    71429,
    76923,
    83333,
    90909,
    100000,
    111111,
    125000,
    142857,
    166667,
    200000,
    250000,
    333333,
    500000,
    // Powers of two from 1s to 32s @ 50% precision
    1000000,
    2000000,
    4000000,
    8000000,
    16000000,
    32000000,
};

// ~50 UMA buckets with high precision from ~100 us to 1s.
const int kUMADurationBuckets[] = {
    // Powers of 2 from 1 us to 64 us @ 50% precision.
    1,
    2,
    4,
    8,
    16,
    32,
    64,
    // 1.25^20, 1.25^21, ..., 1.25^62 @ 20% precision.
    87,
    108,
    136,
    169,
    212,
    265,
    331,
    414,
    517,
    646,
    808,
    1010,
    1262,
    1578,
    1972,
    2465,
    3081,
    3852,
    4815,
    6019,
    7523,
    9404,
    11755,
    14694,
    18367,
    22959,
    28699,
    35873,
    44842,
    56052,
    70065,
    87581,
    109476,
    136846,
    171057,
    213821,
    267276,
    334096,
    417619,
    522024,
    652530,
    815663,
    1019579,
    // Powers of 2 from 2s to 32s @ 50% precision.
    2000000,
    4000000,
    8000000,
    16000000,
    32000000,
};

#define UMA_HISTOGRAM_CUSTOM_TIMES_VSYNC_ALIGNED(name, sample)             \
  do {                                                                     \
    UMA_HISTOGRAM_CUSTOM_ENUMERATION(                                      \
        name "2", sample.InMicroseconds(),                                 \
        std::vector<int>(kUMAVSyncBuckets,                                 \
                         kUMAVSyncBuckets + std::size(kUMAVSyncBuckets))); \
  } while (false)

#define UMA_HISTOGRAM_CUSTOM_TIMES_DURATION_SUFFIX(name, suffix, sample) \
  do {                                                                   \
    UMA_HISTOGRAM_CUSTOM_ENUMERATION(                                    \
        name "2" suffix, sample.InMicroseconds(),                        \
        std::vector<int>(                                                \
            kUMADurationBuckets,                                         \
            kUMADurationBuckets + std::size(kUMADurationBuckets)));      \
  } while (false)

#define UMA_HISTOGRAM_CUSTOM_TIMES_DURATION(name, sample) \
  UMA_HISTOGRAM_CUSTOM_TIMES_DURATION_SUFFIX(name, "", sample)

#define UMA_HISTOGRAM_READY_TO_ACTIVATE(name, sample, priority)            \
  do {                                                                     \
    UMA_HISTOGRAM_CUSTOM_TIMES_DURATION(name, sample);                     \
    switch (priority) {                                                    \
      case SAME_PRIORITY_FOR_BOTH_TREES:                                   \
        UMA_HISTOGRAM_CUSTOM_TIMES_DURATION_SUFFIX(name, ".Same", sample); \
        break;                                                             \
      case SMOOTHNESS_TAKES_PRIORITY:                                      \
        UMA_HISTOGRAM_CUSTOM_TIMES_DURATION_SUFFIX(name, ".Smoothness",    \
                                                   sample);                \
        break;                                                             \
      case NEW_CONTENT_TAKES_PRIORITY:                                     \
        UMA_HISTOGRAM_CUSTOM_TIMES_DURATION_SUFFIX(name, ".NewContent",    \
                                                   sample);                \
        break;                                                             \
    }                                                                      \
  } while (false)

class RendererUMAReporter : public CompositorTimingHistory::UMAReporter {
 public:
  ~RendererUMAReporter() override = default;

  void AddDrawInterval(base::TimeDelta interval) override {
    UMA_HISTOGRAM_CUSTOM_TIMES_VSYNC_ALIGNED("Scheduling.Renderer.DrawInterval",
                                             interval);
  }

  void AddDrawIntervalWithCustomPropertyAnimations(
      base::TimeDelta interval) override {
    UMA_HISTOGRAM_CUSTOM_TIMES_VSYNC_ALIGNED(
        "Scheduling.Renderer.DrawIntervalWithCustomPropertyAnimations",
        interval);
  }

  void AddBeginImplFrameLatency(base::TimeDelta delta) override {
    UMA_HISTOGRAM_CUSTOM_TIMES_DURATION(
        "Scheduling.Renderer.BeginImplFrameLatency", delta);
  }

  void AddDrawDuration(base::TimeDelta duration) override {
    UMA_HISTOGRAM_CUSTOM_TIMES_DURATION("Scheduling.Renderer.DrawDuration",
                                        duration);
  }

  void AddImplFrameDeadlineType(
      CompositorTimingHistory::DeadlineMode deadline_mode) override {
    UMA_HISTOGRAM_ENUMERATION("Scheduling.Renderer.DeadlineMode",
                              deadline_mode);
  }
};

class BrowserUMAReporter : public CompositorTimingHistory::UMAReporter {
 public:
  ~BrowserUMAReporter() override = default;

  // DrawInterval is not meaningful to measure on browser side because
  // browser rendering fps is not at 60.
  void AddDrawInterval(base::TimeDelta interval) override {}

  void AddDrawIntervalWithCustomPropertyAnimations(
      base::TimeDelta interval) override {}

  void AddBeginImplFrameLatency(base::TimeDelta delta) override {
    UMA_HISTOGRAM_CUSTOM_TIMES_DURATION(
        "Scheduling.Browser.BeginImplFrameLatency", delta);
  }

  void AddDrawDuration(base::TimeDelta duration) override {
    UMA_HISTOGRAM_CUSTOM_TIMES_DURATION("Scheduling.Browser.DrawDuration",
                                        duration);
  }

  void AddImplFrameDeadlineType(
      CompositorTimingHistory::DeadlineMode deadline_mode) override {
    // The browser compositor scheduler is synchronous and only has None (or
    // Blocked as edges cases) for deadline mode.
  }
};

class NullUMAReporter : public CompositorTimingHistory::UMAReporter {
 public:
  ~NullUMAReporter() override = default;
  void AddDrawInterval(base::TimeDelta interval) override {}
  void AddDrawIntervalWithCustomPropertyAnimations(
      base::TimeDelta inverval) override {}
  void AddBeginImplFrameLatency(base::TimeDelta delta) override {}
  void AddDrawDuration(base::TimeDelta duration) override {}
  void AddImplFrameDeadlineType(
      CompositorTimingHistory::DeadlineMode deadline_mode) override {}
};

}  // namespace

CompositorTimingHistory::CompositorTimingHistory(
    bool using_synchronous_renderer_compositor,
    UMACategory uma_category,
    RenderingStatsInstrumentation* rendering_stats_instrumentation)
    : using_synchronous_renderer_compositor_(
          using_synchronous_renderer_compositor),
      enabled_(false),
      compositor_drawing_continuously_(false),
      begin_main_frame_queue_duration_history_(kDurationHistorySize),
      begin_main_frame_queue_duration_critical_history_(kDurationHistorySize),
      begin_main_frame_queue_duration_not_critical_history_(
          kDurationHistorySize),
      begin_main_frame_start_to_ready_to_commit_duration_history_(
          kDurationHistorySize),
      commit_duration_history_(kDurationHistorySize),
      commit_to_ready_to_activate_duration_history_(kDurationHistorySize),
      prepare_tiles_duration_history_(kDurationHistorySize),
      activate_duration_history_(kDurationHistorySize),
      draw_duration_history_(kDurationHistorySize),
      duration_estimates_enabled_(base::FeatureList::IsEnabled(
          features::kDurationEstimatesInCompositorTimingHistory)),
      bmf_start_to_ready_to_commit_critical_history_(kDurationHistorySize),
      bmf_start_to_ready_to_commit_critical_percentile_(
          BeginMainFrameStartToReadyToCommitCriticalPercentile()),
      bmf_start_to_ready_to_commit_not_critical_history_(kDurationHistorySize),
      bmf_start_to_ready_to_commit_not_critical_percentile_(
          BeginMainFrameStartToReadyToCommitNonCriticalPercentile()),
      bmf_queue_to_activate_critical_history_(kDurationHistorySize),
      bmf_queue_to_activate_critical_percentile_(
          BeginMainFrameQueueToActivateCriticalPercentile()),
      uma_reporter_(CreateUMAReporter(uma_category)),
      rendering_stats_instrumentation_(rendering_stats_instrumentation) {}

CompositorTimingHistory::~CompositorTimingHistory() = default;

std::unique_ptr<CompositorTimingHistory::UMAReporter>
CompositorTimingHistory::CreateUMAReporter(UMACategory category) {
  switch (category) {
    case RENDERER_UMA:
      return base::WrapUnique(new RendererUMAReporter);
    case BROWSER_UMA:
      return base::WrapUnique(new BrowserUMAReporter);
    case NULL_UMA:
      return base::WrapUnique(new NullUMAReporter);
  }
  NOTREACHED();
  return base::WrapUnique<CompositorTimingHistory::UMAReporter>(nullptr);
}

base::TimeTicks CompositorTimingHistory::Now() const {
  return base::TimeTicks::Now();
}

void CompositorTimingHistory::SetRecordingEnabled(bool enabled) {
  enabled_ = enabled;
}

void CompositorTimingHistory::SetCompositorDrawingContinuously(bool active) {
  if (active == compositor_drawing_continuously_)
    return;
  draw_end_time_prev_ = base::TimeTicks();
  compositor_drawing_continuously_ = active;
}

base::TimeDelta
CompositorTimingHistory::BeginMainFrameQueueDurationCriticalEstimate() const {
  base::TimeDelta all = begin_main_frame_queue_duration_history_.Percentile(
      kBeginMainFrameQueueDurationEstimationPercentile);
  base::TimeDelta critical =
      begin_main_frame_queue_duration_critical_history_.Percentile(
          kBeginMainFrameQueueDurationCriticalEstimationPercentile);
  // Return the min since critical BeginMainFrames are likely fast if
  // the non critical ones are.
  return std::min(critical, all);
}

base::TimeDelta
CompositorTimingHistory::BeginMainFrameQueueDurationNotCriticalEstimate()
    const {
  base::TimeDelta all = begin_main_frame_queue_duration_history_.Percentile(
      kBeginMainFrameQueueDurationEstimationPercentile);
  base::TimeDelta not_critical =
      begin_main_frame_queue_duration_not_critical_history_.Percentile(
          kBeginMainFrameQueueDurationNotCriticalEstimationPercentile);
  // Return the max since, non critical BeginMainFrames are likely slow if
  // the critical ones are.
  return std::max(not_critical, all);
}

base::TimeDelta
CompositorTimingHistory::BeginMainFrameStartToReadyToCommitDurationEstimate()
    const {
  return begin_main_frame_start_to_ready_to_commit_duration_history_.Percentile(
      kBeginMainFrameStartToReadyToCommitEstimationPercentile);
}

base::TimeDelta CompositorTimingHistory::CommitDurationEstimate() const {
  return commit_duration_history_.Percentile(kCommitEstimatePercentile);
}

base::TimeDelta
CompositorTimingHistory::CommitToReadyToActivateDurationEstimate() const {
  return commit_to_ready_to_activate_duration_history_.Percentile(
      kCommitToReadyToActivateEstimationPercentile);
}

base::TimeDelta CompositorTimingHistory::PrepareTilesDurationEstimate() const {
  return prepare_tiles_duration_history_.Percentile(
      kPrepareTilesEstimationPercentile);
}

base::TimeDelta CompositorTimingHistory::ActivateDurationEstimate() const {
  return activate_duration_history_.Percentile(kActivateEstimationPercentile);
}

base::TimeDelta CompositorTimingHistory::DrawDurationEstimate() const {
  return draw_duration_history_.Percentile(kDrawEstimationPercentile);
}

base::TimeDelta
CompositorTimingHistory::BeginMainFrameStartToReadyToCommitCriticalEstimate()
    const {
  if (duration_estimates_enabled_) {
    return bmf_start_to_ready_to_commit_critical_history_.Percentile(
        bmf_start_to_ready_to_commit_critical_percentile_);
  }
  return BeginMainFrameStartToReadyToCommitDurationEstimate() +
         BeginMainFrameQueueDurationCriticalEstimate();
}

base::TimeDelta
CompositorTimingHistory::BeginMainFrameStartToReadyToCommitNotCriticalEstimate()
    const {
  if (duration_estimates_enabled_) {
    return bmf_start_to_ready_to_commit_not_critical_history_.Percentile(
        bmf_start_to_ready_to_commit_not_critical_percentile_);
  }
  return BeginMainFrameStartToReadyToCommitDurationEstimate() +
         BeginMainFrameQueueDurationNotCriticalEstimate();
}

base::TimeDelta
CompositorTimingHistory::BeginMainFrameQueueToActivateCriticalEstimate() const {
  if (duration_estimates_enabled_) {
    return bmf_queue_to_activate_critical_history_.Percentile(
        bmf_queue_to_activate_critical_percentile_);
  }
  return BeginMainFrameStartToReadyToCommitDurationEstimate() +
         CommitDurationEstimate() + CommitToReadyToActivateDurationEstimate() +
         ActivateDurationEstimate() +
         BeginMainFrameQueueDurationCriticalEstimate();
}

void CompositorTimingHistory::WillBeginImplFrame(
    const viz::BeginFrameArgs& args,
    base::TimeTicks now) {
  viz::BeginFrameArgs::BeginFrameArgsType frame_type = args.type;
  base::TimeTicks frame_time = args.frame_time;

  if (frame_type == viz::BeginFrameArgs::NORMAL)
    uma_reporter_->AddBeginImplFrameLatency(now - frame_time);
}

void CompositorTimingHistory::WillFinishImplFrame(bool needs_redraw) {
  if (!needs_redraw)
    SetCompositorDrawingContinuously(false);
}

void CompositorTimingHistory::BeginImplFrameNotExpectedSoon() {
  SetCompositorDrawingContinuously(false);
}

void CompositorTimingHistory::WillBeginMainFrame(
    const viz::BeginFrameArgs& args) {
  DCHECK_EQ(base::TimeTicks(), begin_main_frame_sent_time_);

  begin_main_frame_on_critical_path_ = args.on_critical_path;
  begin_main_frame_sent_time_ = Now();
}

void CompositorTimingHistory::BeginMainFrameStarted(
    base::TimeTicks main_thread_start_time) {
  DCHECK_NE(base::TimeTicks(), begin_main_frame_sent_time_);
  DCHECK_EQ(base::TimeTicks(), begin_main_frame_start_time_);
  begin_main_frame_start_time_ = main_thread_start_time;
}

void CompositorTimingHistory::BeginMainFrameAborted() {
  base::TimeTicks begin_main_frame_end_time = Now();
  DidBeginMainFrame(begin_main_frame_end_time);
}

void CompositorTimingHistory::NotifyReadyToCommit() {
  DCHECK_NE(begin_main_frame_start_time_, base::TimeTicks());
  DCHECK_EQ(ready_to_commit_time_, base::TimeTicks());
  ready_to_commit_time_ = Now();
  pending_commit_on_critical_path_ = begin_main_frame_on_critical_path_;
  if (enabled_ && duration_estimates_enabled_) {
    bmf_start_to_ready_to_activate_duration_ =
        ready_to_commit_time_ - begin_main_frame_start_time_;
  }
  base::TimeDelta bmf_duration =
      ready_to_commit_time_ - begin_main_frame_start_time_;
  DidBeginMainFrame(ready_to_commit_time_);
  begin_main_frame_start_to_ready_to_commit_duration_history_.InsertSample(
      bmf_duration);
  if (enabled_ && duration_estimates_enabled_) {
    if (pending_commit_on_critical_path_) {
      bmf_start_to_ready_to_commit_critical_history_.InsertSample(
          bmf_duration + begin_main_frame_queue_duration_);
    } else {
      bmf_start_to_ready_to_commit_not_critical_history_.InsertSample(
          bmf_duration + begin_main_frame_queue_duration_);
    }
  }
}

void CompositorTimingHistory::WillCommit() {
  DCHECK_NE(ready_to_commit_time_, base::TimeTicks());
  commit_start_time_ = Now();
  if (enabled_ && duration_estimates_enabled_) {
    DCHECK_NE(ready_to_commit_time_, base::TimeTicks());
    bmf_start_to_ready_to_activate_duration_ +=
        commit_start_time_ - ready_to_commit_time_;
  }
  ready_to_commit_time_ = base::TimeTicks();
}

void CompositorTimingHistory::DidCommit() {
  DCHECK_EQ(pending_tree_creation_time_, base::TimeTicks());
  DCHECK_NE(commit_start_time_, base::TimeTicks());

  base::TimeTicks commit_end_time = Now();
  if (enabled_ && duration_estimates_enabled_) {
    pending_tree_on_critical_path_ = pending_commit_on_critical_path_;
    bmf_start_to_ready_to_activate_duration_ +=
        (commit_end_time - commit_start_time_);
  }
  commit_duration_history_.InsertSample(commit_end_time - commit_start_time_);

  pending_tree_is_impl_side_ = false;
  pending_tree_creation_time_ = commit_end_time;
  if (enabled_ && duration_estimates_enabled_)
    pending_tree_bmf_queue_duration_ = begin_main_frame_queue_duration_;
}

void CompositorTimingHistory::DidBeginMainFrame(
    base::TimeTicks begin_main_frame_end_time) {
  DCHECK_NE(base::TimeTicks(), begin_main_frame_sent_time_);

  // If the BeginMainFrame start time isn't known, assume it was immediate
  // for scheduling purposes, but don't report it for UMA to avoid skewing
  // the results.
  // TODO(szager): Can this be true? begin_main_frame_start_time_ should be
  // unconditionally assigned in BeginMainFrameStarted().
  if (begin_main_frame_start_time_.is_null())
    begin_main_frame_start_time_ = begin_main_frame_sent_time_;

  base::TimeDelta bmf_sent_to_commit_duration =
      begin_main_frame_end_time - begin_main_frame_sent_time_;
  base::TimeDelta bmf_queue_duration =
      begin_main_frame_start_time_ - begin_main_frame_sent_time_;

  rendering_stats_instrumentation_->AddBeginMainFrameToCommitDuration(
      bmf_sent_to_commit_duration);

  if (enabled_) {
    begin_main_frame_queue_duration_history_.InsertSample(bmf_queue_duration);
    if (begin_main_frame_on_critical_path_) {
      begin_main_frame_queue_duration_critical_history_.InsertSample(
          bmf_queue_duration);
    } else {
      begin_main_frame_queue_duration_not_critical_history_.InsertSample(
          bmf_queue_duration);
    }
    if (duration_estimates_enabled_)
      begin_main_frame_queue_duration_ = bmf_queue_duration;
  }

  begin_main_frame_sent_time_ = base::TimeTicks();
  begin_main_frame_start_time_ = base::TimeTicks();
  begin_main_frame_on_critical_path_ = false;
}

void CompositorTimingHistory::WillInvalidateOnImplSide() {
  DCHECK(!pending_tree_is_impl_side_);
  DCHECK_EQ(pending_tree_creation_time_, base::TimeTicks());

  pending_tree_is_impl_side_ = true;
  pending_tree_on_critical_path_ = false;
  pending_tree_bmf_queue_duration_ = base::TimeDelta();
  pending_tree_creation_time_ = base::TimeTicks::Now();
}

void CompositorTimingHistory::WillPrepareTiles() {
  DCHECK_EQ(base::TimeTicks(), prepare_tiles_start_time_);
  prepare_tiles_start_time_ = Now();
}

void CompositorTimingHistory::DidPrepareTiles() {
  DCHECK_NE(base::TimeTicks(), prepare_tiles_start_time_);

  base::TimeDelta prepare_tiles_duration = Now() - prepare_tiles_start_time_;
  if (enabled_)
    prepare_tiles_duration_history_.InsertSample(prepare_tiles_duration);

  prepare_tiles_start_time_ = base::TimeTicks();
}

void CompositorTimingHistory::ReadyToActivate() {
  DCHECK_NE(pending_tree_creation_time_, base::TimeTicks());
  DCHECK_EQ(pending_tree_ready_to_activate_time_, base::TimeTicks());

  pending_tree_ready_to_activate_time_ = Now();
  if (!pending_tree_is_impl_side_) {
    base::TimeDelta time_since_commit =
        pending_tree_ready_to_activate_time_ - pending_tree_creation_time_;

    // Before adding the new data point to the timing history, see what we would
    // have predicted for this frame. This allows us to keep track of the
    // accuracy of our predictions.

    base::TimeDelta commit_to_ready_to_activate_estimate =
        CommitToReadyToActivateDurationEstimate();
    rendering_stats_instrumentation_->AddCommitToActivateDuration(
        time_since_commit, commit_to_ready_to_activate_estimate);

    if (enabled_) {
      commit_to_ready_to_activate_duration_history_.InsertSample(
          time_since_commit);
      if (duration_estimates_enabled_)
        bmf_start_to_ready_to_activate_duration_ += time_since_commit;
    }
  }
}

void CompositorTimingHistory::WillActivate() {
  DCHECK_EQ(base::TimeTicks(), activate_start_time_);

  activate_start_time_ = Now();

  pending_tree_is_impl_side_ = false;
  pending_tree_creation_time_ = base::TimeTicks();
}

void CompositorTimingHistory::DidActivate() {
  DCHECK_NE(base::TimeTicks(), activate_start_time_);
  base::TimeTicks activate_end_time = Now();
  base::TimeDelta activate_duration = activate_end_time - activate_start_time_;

  if (enabled_) {
    activate_duration_history_.InsertSample(activate_duration);

    if (duration_estimates_enabled_) {
      if (pending_tree_on_critical_path_) {
        base::TimeDelta time_since_ready_to_activate =
            activate_end_time - pending_tree_ready_to_activate_time_;
        DCHECK_NE(pending_tree_bmf_queue_duration_, base::TimeDelta());
        bmf_queue_to_activate_critical_history_.InsertSample(
            bmf_start_to_ready_to_activate_duration_ +
            time_since_ready_to_activate + pending_tree_bmf_queue_duration_);
      }
      bmf_start_to_ready_to_activate_duration_ = base::TimeDelta();
      pending_tree_on_critical_path_ = false;
    }
  }

  pending_tree_ready_to_activate_time_ = base::TimeTicks();
  activate_start_time_ = base::TimeTicks();
}

void CompositorTimingHistory::WillDraw() {
  DCHECK_EQ(base::TimeTicks(), draw_start_time_);
  draw_start_time_ = Now();
}

void CompositorTimingHistory::DidDraw(bool used_new_active_tree,
                                      bool has_custom_property_animations) {
  DCHECK_NE(base::TimeTicks(), draw_start_time_);
  base::TimeTicks draw_end_time = Now();
  base::TimeDelta draw_duration = draw_end_time - draw_start_time_;

  // Before adding the new data point to the timing history, see what we would
  // have predicted for this frame. This allows us to keep track of the accuracy
  // of our predictions.
  base::TimeDelta draw_estimate = DrawDurationEstimate();
  rendering_stats_instrumentation_->AddDrawDuration(draw_duration,
                                                    draw_estimate);

  uma_reporter_->AddDrawDuration(draw_duration);

  if (enabled_) {
    draw_duration_history_.InsertSample(draw_duration);
  }

  SetCompositorDrawingContinuously(true);
  if (!draw_end_time_prev_.is_null()) {
    base::TimeDelta draw_interval = draw_end_time - draw_end_time_prev_;
    uma_reporter_->AddDrawInterval(draw_interval);
    // Emit a trace event to highlight a long time lapse between the draw times
    // of back-to-back BeginImplFrames.
    if (draw_interval > kDrawIntervalTraceThreshold) {
      TRACE_EVENT_NESTABLE_ASYNC_BEGIN_WITH_TIMESTAMP0(
          "latency", "Long Draw Interval",
          TRACE_ID_WITH_SCOPE("Long Draw Interval", g_num_long_draw_intervals),
          draw_start_time_);
      TRACE_EVENT_NESTABLE_ASYNC_END_WITH_TIMESTAMP0(
          "latency", "Long Draw Interval",
          TRACE_ID_WITH_SCOPE("Long Draw Interval", g_num_long_draw_intervals),
          draw_end_time);
      g_num_long_draw_intervals++;
    }
    if (has_custom_property_animations &&
        previous_frame_had_custom_property_animations_)
      uma_reporter_->AddDrawIntervalWithCustomPropertyAnimations(draw_interval);
  }
  previous_frame_had_custom_property_animations_ =
      has_custom_property_animations;
  draw_end_time_prev_ = draw_end_time;

  if (used_new_active_tree)
    new_active_tree_draw_end_time_prev_ = draw_end_time;
  draw_start_time_ = base::TimeTicks();
}

void CompositorTimingHistory::RecordDeadlineMode(DeadlineMode deadline_mode) {
  if (uma_reporter_)
    uma_reporter_->AddImplFrameDeadlineType(deadline_mode);
}

void CompositorTimingHistory::ClearHistory() {
  TRACE_EVENT0("cc,benchmark", "CompositorTimingHistory::ClearHistory");

  begin_main_frame_queue_duration_history_.Clear();
  begin_main_frame_queue_duration_critical_history_.Clear();
  begin_main_frame_queue_duration_not_critical_history_.Clear();
  begin_main_frame_start_to_ready_to_commit_duration_history_.Clear();
  commit_duration_history_.Clear();
  commit_to_ready_to_activate_duration_history_.Clear();
  prepare_tiles_duration_history_.Clear();
  activate_duration_history_.Clear();
  draw_duration_history_.Clear();
  bmf_start_to_ready_to_commit_critical_history_.Clear();
  bmf_start_to_ready_to_commit_not_critical_history_.Clear();
  bmf_queue_to_activate_critical_history_.Clear();
}

size_t CompositorTimingHistory::CommitDurationSampleCountForTesting() const {
  return commit_duration_history_.sample_count();
}
}  // namespace cc