Use pacing info in ProbeBitrateEstimator to validate probe results.

webrtc/modules/congestion_controller/probe_bitrate_estimator.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/probe_bitrate_estimator.h"
 
 #include <algorithm>
 
 #include "webrtc/base/checks.h"
 #include "webrtc/base/logging.h"
 
 namespace {
 // The minumum number of probes we need for a valid cluster.

[Sergey Ulanov, 2017/03/08 22:12:20]

Update this comment (e.g. "Portion of successful probes in a cluster for a valid
probe.")?

[philipel, 2017/03/09 11:47:41]

Done.

-constexpr int kMinNumProbesValidCluster = 4;
+constexpr float kMinReceivedProbesRatio = 4.0 / 5.0;

[Sergey Ulanov, 2017/03/08 22:12:20]

0.8?

[philipel, 2017/03/09 11:47:41]

Changed to int instead.

+
+// The minumum number of bytes we need for a valid cluster.

[Sergey Ulanov, 2017/03/08 22:12:20]

rephrase this comment as well please. It's a ratio, not number of bytes.

[philipel, 2017/03/09 11:47:41]

Done.

+constexpr float kMinReceivedBytesRatio = 4.0 / 5.0;
 
 // The maximum (receive rate)/(send rate) ratio for a valid estimate.
 constexpr float kValidRatio = 2.0f;
 
 // The maximum time period over which the cluster history is retained.
 // This is also the maximum time period beyond which a probing burst is not
 // expected to last.
 constexpr int kMaxClusterHistoryMs = 1000;
 
 // The maximum time interval between first and the last probe on a cluster
@@ skipping 25 matching lines @@
   if (packet_info.arrival_time_ms < cluster->first_receive_ms) {
     cluster->first_receive_ms = packet_info.arrival_time_ms;
     cluster->size_first_receive = payload_size_bits;
   }
   if (packet_info.arrival_time_ms > cluster->last_receive_ms) {
     cluster->last_receive_ms = packet_info.arrival_time_ms;
   }
   cluster->size_total += payload_size_bits;
   cluster->num_probes += 1;
 
-  if (cluster->num_probes < kMinNumProbesValidCluster)
+  RTC_DCHECK_GT(packet_info.pacing_info.probe_cluster_min_probes, 0);
+  RTC_DCHECK_GT(packet_info.pacing_info.probe_cluster_min_bytes, 0);
+
+  int min_probes =
+      static_cast<int>(packet_info.pacing_info.probe_cluster_min_probes *

[terelius, 2017/03/08 15:55:11]

This might not be rounded correctly. kMinReceivedProbesRatio is not exactly
representable as a float.

[Sergey Ulanov, 2017/03/08 22:12:20]

maybe use integer percentage value (4/5 = 80%)? Then this calculation can be
done without float.

[philipel, 2017/03/09 11:47:41]

True, switched to int as Sergey suggested.

[philipel, 2017/03/09 11:47:41]

Good idea, implemented!

+                       kMinReceivedProbesRatio);
+  int min_bytes = static_cast<int>(

[terelius, 2017/03/08 15:55:11]

This might not be rounded correctly. kMinReceivedBytesRatio is not exactly
representable as a float.

+      packet_info.pacing_info.probe_cluster_min_bytes * kMinReceivedBytesRatio);
+  if (cluster->num_probes < min_probes || cluster->size_total < min_bytes * 8)
     return -1;
 
   float send_interval_ms = cluster->last_send_ms - cluster->first_send_ms;
   float receive_interval_ms =
       cluster->last_receive_ms - cluster->first_receive_ms;
 
   if (send_interval_ms <= 0 || send_interval_ms > kMaxProbeIntervalMs ||
       receive_interval_ms <= 0 || receive_interval_ms > kMaxProbeIntervalMs) {
     LOG(LS_INFO) << "Probing unsuccessful, invalid send/receive interval"
                  << " [cluster id: " << cluster_id
@@ skipping 42 matching lines @@
 void ProbeBitrateEstimator::EraseOldClusters(int64_t timestamp_ms) {
   for (auto it = clusters_.begin(); it != clusters_.end();) {
     if (it->second.last_receive_ms < timestamp_ms) {
       it = clusters_.erase(it);
     } else {
       ++it;
     }
   }
 }
 }  // namespace webrtc