Only use 95% of the link capacity if the true link capacity is found by probing.

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.
  */
 
@@ skipping 186 matching lines @@
       probe_bitrate_estimator_.FetchAndResetLastEstimatedBitrateBps();
   // Currently overusing the bandwidth.
   if (overusing) {
     if (acked_bitrate_bps &&
         rate_control_.TimeToReduceFurther(now_ms, *acked_bitrate_bps)) {
       result.updated = UpdateEstimate(now_ms, acked_bitrate_bps, overusing,
                                       &result.target_bitrate_bps);
     }
   } else {
     if (probe_bitrate_bps) {
+      result.probe = true;
+      result.updated = true;
+      result.target_bitrate_bps = *probe_bitrate_bps;
       rate_control_.SetEstimate(*probe_bitrate_bps, now_ms);
-      result.probe = true;
+    } else {
+      result.updated = UpdateEstimate(now_ms, acked_bitrate_bps, overusing,
+                                      &result.target_bitrate_bps);
     }
-    result.updated = UpdateEstimate(now_ms, acked_bitrate_bps, overusing,
-                                    &result.target_bitrate_bps);
   }
   if (result.updated) {
     BWE_TEST_LOGGING_PLOT(1, "target_bitrate_bps", now_ms,
                           result.target_bitrate_bps);
     if (event_log_ && (result.target_bitrate_bps != last_logged_bitrate_ ||
                        detector_.State() != last_logged_state_)) {
       event_log_->LogDelayBasedBweUpdate(result.target_bitrate_bps,
                                          detector_.State());
       last_logged_bitrate_ = result.target_bitrate_bps;
       last_logged_state_ = detector_.State();
     }
   }
   return result;
 }
 
 bool DelayBasedBwe::UpdateEstimate(int64_t now_ms,
                                    rtc::Optional<uint32_t> acked_bitrate_bps,
                                    bool overusing,
                                    uint32_t* target_bitrate_bps) {
   // TODO(terelius): RateControlInput::noise_var is deprecated and will be
   // removed. In the meantime, we set it to zero.
   const RateControlInput input(
       overusing ? BandwidthUsage::kBwOverusing : detector_.State(),
       acked_bitrate_bps, 0);
+  uint32_t prev_target_bitrate_bps = rate_control_.LatestEstimate();
   *target_bitrate_bps = rate_control_.Update(&input, now_ms);
-  return rate_control_.ValidEstimate();
+  return rate_control_.ValidEstimate() &&
+         prev_target_bitrate_bps != *target_bitrate_bps;
 }
 
 void DelayBasedBwe::OnRttUpdate(int64_t avg_rtt_ms, int64_t max_rtt_ms) {
   rate_control_.SetRtt(avg_rtt_ms);
 }
 
 bool DelayBasedBwe::LatestEstimate(std::vector<uint32_t>* ssrcs,
                                    uint32_t* bitrate_bps) const {
   // Currently accessed from both the process thread (see
   // ModuleRtpRtcpImpl::Process()) and the configuration thread (see
@@ skipping 17 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::GetExpectedBwePeriodMs() const {
   return rate_control_.GetExpectedBandwidthPeriodMs();
 }
 }  // namespace webrtc