Add logging of delay-based bandwidth estimate.

webrtc/modules/congestion_controller/delay_based_bwe.cc

 /*
  *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 #include "webrtc/modules/congestion_controller/delay_based_bwe.h"
 
 #include <algorithm>
 #include <cmath>
 #include <string>
 
 #include "webrtc/base/checks.h"
 #include "webrtc/base/constructormagic.h"
 #include "webrtc/base/logging.h"
 #include "webrtc/base/thread_annotations.h"
+#include "webrtc/logging/rtc_event_log/rtc_event_log.h"
 #include "webrtc/modules/congestion_controller/include/congestion_controller.h"
 #include "webrtc/modules/pacing/paced_sender.h"
 #include "webrtc/modules/remote_bitrate_estimator/include/remote_bitrate_estimator.h"
 #include "webrtc/modules/remote_bitrate_estimator/test/bwe_test_logging.h"
 #include "webrtc/system_wrappers/include/field_trial.h"
 #include "webrtc/system_wrappers/include/metrics.h"
 #include "webrtc/typedefs.h"
 
 namespace {
 constexpr int kTimestampGroupLengthMs = 5;
@@ skipping 170 matching lines @@
   sum_ += bytes;
   return bitrate_sample;
 }
 
 rtc::Optional<uint32_t> DelayBasedBwe::BitrateEstimator::bitrate_bps() const {
   if (bitrate_estimate_ < 0.f)
     return rtc::Optional<uint32_t>();
   return rtc::Optional<uint32_t>(bitrate_estimate_ * 1000);
 }
 
-DelayBasedBwe::DelayBasedBwe(Clock* clock)
+DelayBasedBwe::DelayBasedBwe(RtcEventLog* event_log, Clock* clock)
     : in_trendline_experiment_(TrendlineFilterExperimentIsEnabled()),
       in_median_slope_experiment_(MedianSlopeFilterExperimentIsEnabled()),
+      event_log_(event_log),
       clock_(clock),
       inter_arrival_(),
       kalman_estimator_(),
       trendline_estimator_(),
       detector_(),
       receiver_incoming_bitrate_(),
       last_update_ms_(-1),
       last_seen_packet_ms_(-1),
       uma_recorded_(false),
       trendline_window_size_(kDefaultTrendlineWindowSize),
@@ skipping 158 matching lines @@
       (last_update_ms_ == -1 ||
        now_ms - last_update_ms_ > rate_control_.GetFeedbackInterval())) {
     result.updated =
         UpdateEstimate(info.arrival_time_ms, now_ms, acked_bitrate_bps,
                        &result.target_bitrate_bps);
   }
   if (result.updated) {
     last_update_ms_ = now_ms;
     BWE_TEST_LOGGING_PLOT(1, "target_bitrate_bps", now_ms,
                           result.target_bitrate_bps);
+    if (event_log_) {

[stefan-webrtc, 2017/02/14 18:13:20]

Should we pass a null object instead?

[terelius, 2017/02/15 12:49:24]

I don't know. We use a null implementation in some places, but the RPT and RTCP
senders explicitly check for null pointers. WDYT?

[stefan-webrtc, 2017/02/16 10:22:28]

I tend to prefer null objects, but I don't feel that strongly about it.

+      event_log_->LogBwePacketDelayEvent(result.target_bitrate_bps,
+                                         detector_.State());
+    }
   }
 
   return result;
 }
 
 bool DelayBasedBwe::UpdateEstimate(int64_t arrival_time_ms,
                                    int64_t now_ms,
                                    rtc::Optional<uint32_t> acked_bitrate_bps,
                                    uint32_t* target_bitrate_bps) {
   // TODO(terelius): RateControlInput::noise_var is deprecated and will be
@@ skipping 32 matching lines @@
 void DelayBasedBwe::SetMinBitrate(int min_bitrate_bps) {
   // Called from both the configuration thread and the network thread. Shouldn't
   // be called from the network thread in the future.
   rate_control_.SetMinBitrate(min_bitrate_bps);
 }
 
 int64_t DelayBasedBwe::GetProbingIntervalMs() const {
   return probing_interval_estimator_.GetIntervalMs();
 }
 }  // namespace webrtc