Add metrics for tracking underflow during src= playback.

media/blink/webmediaplayer_impl.cc

 // Copyright 2013 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/blink/webmediaplayer_impl.h"
 
 #include <algorithm>
 #include <cmath>
 #include <limits>
 #include <string>
@@ skipping 207 matching lines @@
 #if defined(OS_ANDROID)  // WMPI_CAST
       cast_impl_(this, client_, params.context_3d_cb()),
 #endif
       volume_(1.0),
       volume_multiplier_(1.0),
       renderer_factory_(std::move(renderer_factory)),
       surface_manager_(params.surface_manager()),
       overlay_surface_id_(SurfaceManager::kNoSurfaceID),
       suppress_destruction_errors_(false),
       can_suspend_state_(CanSuspendState::UNKNOWN),
-      is_encrypted_(false) {
+      is_encrypted_(false),
+      underflow_count_(0) {
   DCHECK(!adjust_allocated_memory_cb_.is_null());
   DCHECK(renderer_factory_);
   DCHECK(client_);
 
   force_video_overlays_ = base::CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kForceVideoOverlays);
 
   if (delegate_)
     delegate_id_ = delegate_->AddObserver(this);
 
@@ skipping 852 matching lines @@
     if (data_source_)
       data_source_->OnBufferingHaveEnough(false);
 
     // Blink expects a timeChanged() in response to a seek().
     if (should_notify_time_changed_)
       client_->timeChanged();
 
     // Once we have enough, start reporting the total memory usage. We'll also
     // report once playback starts.
     ReportMemoryUsage();
+
+    // Report the amount of time it took to leave the underflow state. Don't
+    // bother to report this for MSE playbacks since it's out of our control.
+    if (underflow_timer_ && data_source_) {
+      UMA_HISTOGRAM_TIMES("Media.UnderflowDuration",
+                          underflow_timer_->Elapsed());
+      underflow_timer_.reset();
+    }
   } else {
     // Buffering has underflowed.
     DCHECK_EQ(state, BUFFERING_HAVE_NOTHING);
     // It shouldn't be possible to underflow if we've not advanced past
     // HAVE_CURRENT_DATA.
     DCHECK_GT(highest_ready_state_, WebMediaPlayer::ReadyStateHaveCurrentData);
     SetReadyState(WebMediaPlayer::ReadyStateHaveCurrentData);
+
+    // Report the number of times we've entered the underflow state. Only report
+    // for src= playback since for MSE it's out of our control.
+    if (data_source_) {
+      UMA_HISTOGRAM_COUNTS_100("Media.UnderflowCount", ++underflow_count_);
+      underflow_timer_.reset(new base::ElapsedTimer());
+    }
   }
 
   UpdatePlayState();
 }
 
 void WebMediaPlayerImpl::OnDurationChange() {
   DCHECK(main_task_runner_->BelongsToCurrentThread());
 
   // TODO(sandersd): We should call delegate_->DidPlay() with the new duration,
   // especially if it changed from  <5s to >5s.
@@ skipping 672 matching lines @@
       pipeline_metadata_.natural_size,
       base::Bind(&GetCurrentTimeInternal, this)));
   watch_time_reporter_->OnVolumeChange(volume_);
   if (delegate_ && delegate_->IsHidden())
     watch_time_reporter_->OnHidden();
   else
     watch_time_reporter_->OnShown();
 }
 
 }  // namespace media