Media Remoting: UMAs to track session events and measurements.

media/remoting/metrics.cc

+// Copyright 2017 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 "media/remoting/metrics.h"
+
+#include "base/metrics/histogram_macros.h"
+#include "media/audio/sample_rates.h"
+
+namespace media {
+namespace remoting {
+
+namespace {
+
+////////////////////////////////////////////////////////////////////////////////
+// BEGIN: These were all borrowed from src/media/filter/ffmpeg_demuxer.cc.
+// TODO(miu): This code will be de-duped in a soon-upcoming change.
+
+// Some videos just want to watch the world burn, with a height of 0; cap the
+// "infinite" aspect ratio resulting.
+constexpr int kInfiniteRatio = 99999;
+
+// Common aspect ratios (multiplied by 100 and truncated) used for histogramming
+// video sizes.  These were taken on 20111103 from
+// http://wikipedia.org/wiki/Aspect_ratio_(image)#Previous_and_currently_used_aspect_ratios
+constexpr int kCommonAspectRatios100[] = {
+    100, 115, 133, 137, 143, 150, 155, 160,  166,
+    175, 177, 185, 200, 210, 220, 221, 235,  237,
+    240, 255, 259, 266, 276, 293, 400, 1200, kInfiniteRatio,
+};
+
+void UmaHistogramAspectRatio(const char* name, const gfx::Size& size) {
+  UMA_HISTOGRAM_CUSTOM_ENUMERATION(
+      name,

[Steven Holte, 2017/01/17 19:40:11]

This macro uses a static pointer, so you can't use it with a variable name.  You
can either use base::CustomHistogram::FactoryGet directly or convert this into
another macro.

[miu, 2017/01/17 21:09:18]

Ah! Good catch. Fixed. I realized I was just using these in one place, so I
inlined the code.

(Looks like the code in the file I borrowed this from is okay, since it's only
used in one place. I'll fix that in the follow-up CL.)

+      // Intentionally use integer division to truncate the result.
+      size.height() ? (size.width() * 100) / size.height() : kInfiniteRatio,
+      base::CustomHistogram::ArrayToCustomRanges(
+          kCommonAspectRatios100, arraysize(kCommonAspectRatios100)));
+}
+
+// END: Code borrowed from src/media/filter/ffmpeg_demuxer.cc.
+////////////////////////////////////////////////////////////////////////////////
+
+// Buckets for video width histograms.
+constexpr int kVideoWidthBuckets[] = {
+    180,  240,  320,  480,  640,  720,  872,  940,   1280,
+    1440, 1600, 1760, 1920, 2560, 3840, 7680, 16384,
+};
+
+void UmaHistogramVideoWidth(const char* name, const gfx::Size& size) {
+  UMA_HISTOGRAM_CUSTOM_ENUMERATION(

[Steven Holte, 2017/01/17 19:40:11]

Ditto.

[miu, 2017/01/17 21:09:18]

Done.

+      name, size.width(),
+      base::CustomHistogram::ArrayToCustomRanges(
+          kVideoWidthBuckets, arraysize(kVideoWidthBuckets)));
+}
+
+}  // namespace
+
+SessionMetricsRecorder::SessionMetricsRecorder()
+    : last_audio_codec_(kUnknownAudioCodec),
+      last_channel_layout_(CHANNEL_LAYOUT_NONE),
+      last_sample_rate_(0),
+      last_video_codec_(kUnknownVideoCodec),
+      last_video_profile_(VIDEO_CODEC_PROFILE_UNKNOWN),
+      remote_playback_is_disabled_(false) {}
+
+SessionMetricsRecorder::~SessionMetricsRecorder() = default;
+
+void SessionMetricsRecorder::WillStartSession(StartTrigger trigger) {
+  DCHECK(!start_trigger_);
+  start_trigger_ = trigger;
+  start_time_ = base::TimeTicks::Now();
+}
+
+void SessionMetricsRecorder::DidStartSession() {
+  UMA_HISTOGRAM_ENUMERATION("Media.Remoting.SessionStartTrigger",
+                            *start_trigger_, START_TRIGGER_MAX + 1);
+  if (last_audio_codec_ != kUnknownAudioCodec)
+    RecordAudioConfiguration();
+  if (last_video_codec_ != kUnknownVideoCodec)
+    RecordVideoConfiguration();
+  RecordTrackConfiguration();
+}
+
+void SessionMetricsRecorder::WillStopSession(StopTrigger trigger) {
+  if (!start_trigger_)
+    return;
+
+  // Record what triggered the end of the session.
+  UMA_HISTOGRAM_ENUMERATION("Media.Remoting.SessionStopTrigger", trigger,
+                            STOP_TRIGGER_MAX + 1);
+
+  // Record the session duration.

[xjz, 2017/01/17 05:36:25]

nit: DCHECK(!start_time_.is_null());

[miu, 2017/01/17 21:09:18]

I left it out because I think it's pretty obvious it should be set
(start_trigger_ is being checked a few lines above). I usually use DCHECK() for
logic assumptions that may not be clear.

+  const base::TimeDelta session_duration = base::TimeTicks::Now() - start_time_;
+  UMA_HISTOGRAM_CUSTOM_TIMES("Media.Remoting.SessionDuration", session_duration,
+                             base::TimeDelta::FromSeconds(15),
+                             base::TimeDelta::FromHours(12), 50);
+
+  // Reset |start_trigger_| since metrics recording of the current remoting
+  // session has now completed.
+  start_trigger_ = base::nullopt;
+}
+
+void SessionMetricsRecorder::OnPipelineMetadataChanged(
+    const PipelineMetadata& metadata) {
+  if (metadata.has_audio && metadata.audio_decoder_config.IsValidConfig()) {
+    const auto& config = metadata.audio_decoder_config;
+    // While in a remoting session, record audio configuration changes.
+    const bool need_to_record_audio_configuration =
+        start_trigger_ && (config.codec() != last_audio_codec_ ||
+                           config.channel_layout() != last_channel_layout_ ||
+                           config.samples_per_second() != last_sample_rate_);
+    last_audio_codec_ = config.codec();
+    last_channel_layout_ = config.channel_layout();
+    last_sample_rate_ = config.samples_per_second();
+    if (need_to_record_audio_configuration)
+      RecordAudioConfiguration();
+  } else {
+    last_audio_codec_ = kUnknownAudioCodec;
+    last_channel_layout_ = CHANNEL_LAYOUT_NONE;
+    last_sample_rate_ = 0;
+  }
+
+  if (metadata.has_video && metadata.video_decoder_config.IsValidConfig()) {
+    const auto& config = metadata.video_decoder_config;
+    // While in a remoting session, record video configuration changes.
+    const bool need_to_record_video_configuration =
+        start_trigger_ && (config.codec() != last_video_codec_ ||
+                           config.profile() != last_video_profile_ ||
+                           config.natural_size() != last_natural_size_);

[xjz, 2017/01/17 05:36:25]

Do we want to record the change of natural size? Currently
audio/video_decoder_config is only reported once, but the change on natural size
is reported in metadata.natural_size. So maybe we can check:
metadata.natural_size != last_natural_size here. 

[miu, 2017/01/17 21:09:18]

Done. Yes, that's the better one to use.

+    last_video_codec_ = config.codec();
+    last_video_profile_ = config.profile();
+    last_natural_size_ = config.natural_size();

[xjz, 2017/01/17 05:36:25]

As commented above, maybe s/config.natural_size()/metadata.natural_size?

[miu, 2017/01/17 21:09:18]

Done.

+    if (need_to_record_video_configuration)
+      RecordVideoConfiguration();
+  } else {
+    last_video_codec_ = kUnknownVideoCodec;
+    last_video_profile_ = VIDEO_CODEC_PROFILE_UNKNOWN;
+    last_natural_size_ = gfx::Size();
+  }
+
+  // While in a remoting session, record whether audio or video media streams
+  // started or ended.
+  if (start_trigger_)
+    RecordTrackConfiguration();
+}
+
+void SessionMetricsRecorder::OnRemotePlaybackDisabled(bool disabled) {
+  if (disabled == remote_playback_is_disabled_)
+    return;  // De-dupe redundant notifications.
+  UMA_HISTOGRAM_BOOLEAN("Media.Remoting.AllowedByPage", !disabled);
+  remote_playback_is_disabled_ = disabled;
+}
+
+void SessionMetricsRecorder::OnPosterImageDownloaded(
+    base::TimeDelta download_duration,
+    bool success) {
+  const auto name = success ? "Media.Remoting.PosterDownloadDuration.Success"
+                            : "Media.Remoting.PosterDownloadDuration.Fail";
+  UMA_HISTOGRAM_CUSTOM_TIMES(name, download_duration,

[Steven Holte, 2017/01/17 19:40:11]

Ditto.  For this one you can use UmaHistogramCustomTimes from
histogram_functions.h instead.

[miu, 2017/01/17 21:09:18]

Done.

+                             base::TimeDelta::FromMilliseconds(10),
+                             base::TimeDelta::FromSeconds(30), 50);
+}
+
+void SessionMetricsRecorder::RecordAudioConfiguration() {
+  UMA_HISTOGRAM_ENUMERATION("Media.Remoting.AudioCodec", last_audio_codec_,
+                            kAudioCodecMax + 1);
+  UMA_HISTOGRAM_ENUMERATION("Media.Remoting.AudioChannelLayout",
+                            last_channel_layout_, CHANNEL_LAYOUT_MAX + 1);
+  AudioSampleRate asr;
+  if (ToAudioSampleRate(last_sample_rate_, &asr)) {
+    UMA_HISTOGRAM_ENUMERATION("Media.Remoting.AudioSamplesPerSecond", asr,
+                              kAudioSampleRateMax + 1);
+  } else {
+    UMA_HISTOGRAM_COUNTS_1M("Media.Remoting.AudioSamplesPerSecondUnexpected",
+                            last_sample_rate_);
+  }
+}
+
+void SessionMetricsRecorder::RecordVideoConfiguration() {
+  UMA_HISTOGRAM_ENUMERATION("Media.Remoting.VideoCodec", last_video_codec_,
+                            kVideoCodecMax + 1);
+  UMA_HISTOGRAM_ENUMERATION("Media.Remoting.VideoCodecProfile",
+                            last_video_profile_, VIDEO_CODEC_PROFILE_MAX + 1);
+  UmaHistogramVideoWidth("Media.Remoting.VideoNaturalWidth",
+                         last_natural_size_);
+  UmaHistogramAspectRatio("Media.Remoting.VideoAspectRatio",
+                          last_natural_size_);
+}
+
+void SessionMetricsRecorder::RecordTrackConfiguration() {
+  TrackConfiguration config = NEITHER_AUDIO_NOR_VIDEO;
+  if (last_audio_codec_ != kUnknownAudioCodec)
+    config = AUDIO_ONLY;
+  if (last_video_codec_ != kUnknownVideoCodec) {
+    if (config == AUDIO_ONLY)
+      config = AUDIO_AND_VIDEO;
+    else
+      config = VIDEO_ONLY;
+  }
+  UMA_HISTOGRAM_ENUMERATION("Media.Remoting.TrackConfiguration", config,
+                            TRACK_CONFIGURATION_MAX + 1);
+}
+
+RendererMetricsRecorder::RendererMetricsRecorder()
+    : start_time_(base::TimeTicks::Now()), did_record_first_playout_(false) {}
+
+RendererMetricsRecorder::~RendererMetricsRecorder() = default;
+
+void RendererMetricsRecorder::OnRendererInitialized() {
+  const base::TimeDelta elapsed_since_start =
+      base::TimeTicks::Now() - start_time_;
+  UMA_HISTOGRAM_CUSTOM_TIMES("Media.Remoting.TimeUntilRemoteInitialized",
+                             elapsed_since_start,
+                             base::TimeDelta::FromMilliseconds(10),
+                             base::TimeDelta::FromSeconds(30), 50);
+}
+
+void RendererMetricsRecorder::OnEvidenceOfPlayoutAtReceiver() {
+  if (did_record_first_playout_)
+    return;
+  const base::TimeDelta elapsed_since_start =
+      base::TimeTicks::Now() - start_time_;
+  UMA_HISTOGRAM_CUSTOM_TIMES("Media.Remoting.TimeUntilFirstPlayout",
+                             elapsed_since_start,
+                             base::TimeDelta::FromMilliseconds(10),
+                             base::TimeDelta::FromSeconds(30), 50);
+  did_record_first_playout_ = true;
+}
+
+void RendererMetricsRecorder::OnAudioRateEstimate(int kilobits_per_second) {
+  UMA_HISTOGRAM_CUSTOM_COUNTS("Media.Remoting.AudioBitrate",
+                              kilobits_per_second, 1, 1024, 50);
+}
+
+void RendererMetricsRecorder::OnVideoRateEstimate(int kilobits_per_second) {
+  UMA_HISTOGRAM_CUSTOM_COUNTS("Media.Remoting.VideoBitrate",
+                              kilobits_per_second, 1, 16 * 1024, 50);
+}
+
+}  // namespace remoting
+}  // namespace media