Limit QUIC's send algorithm max CWND by the peer's receive buffer and

net/quic/quic_sent_packet_manager.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 "net/quic/quic_sent_packet_manager.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/stl_util.h"
@@ skipping 154 matching lines @@
     use_new_rto_ = true;
   }
   if (config.HasReceivedConnectionOptions() &&
       ContainsQuicTag(config.ReceivedConnectionOptions(), kTIME)) {
     loss_algorithm_.reset(LossDetectionInterface::Create(kTime));
   }
   if (config.HasReceivedSocketReceiveBuffer()) {
     receive_buffer_bytes_ =
         max(kMinSocketReceiveBuffer,
             static_cast<QuicByteCount>(config.ReceivedSocketReceiveBuffer()));
+    if (FLAGS_quic_limit_max_cwnd_to_receive_buffer) {
+      send_algorithm_->SetMaxCongestionWindow(receive_buffer_bytes_ *
+                                              kUsableRecieveBufferFraction);
+    }
   }
   send_algorithm_->SetFromConfig(config, perspective_, using_pacing_);
 
   if (network_change_visitor_ != nullptr) {
     network_change_visitor_->OnCongestionWindowChange();
   }
 }
 
 bool QuicSentPacketManager::ResumeConnectionState(
     const CachedNetworkParameters& cached_network_params) {
@@ skipping 599 matching lines @@
 }
 
 QuicTime::Delta QuicSentPacketManager::TimeUntilSend(
     QuicTime now,
     HasRetransmittableData retransmittable) {
   // The TLP logic is entirely contained within QuicSentPacketManager, so the
   // send algorithm does not need to be consulted.
   if (pending_timer_transmission_count_ > 0) {
     return QuicTime::Delta::Zero();
   }
-  if (unacked_packets_.bytes_in_flight() >=
-      kUsableRecieveBufferFraction * receive_buffer_bytes_) {
+  if (!FLAGS_quic_limit_max_cwnd_to_receive_buffer &&
+      unacked_packets_.bytes_in_flight() >=
+          kUsableRecieveBufferFraction * receive_buffer_bytes_) {
     return QuicTime::Delta::Infinite();
   }
   return send_algorithm_->TimeUntilSend(
       now, unacked_packets_.bytes_in_flight(), retransmittable);
 }
 
 // Uses a 25ms delayed ack timer. Also helps with better signaling
 // in low-bandwidth (< ~384 kbps), where an ack is sent per packet.
 // Ensures that the Delayed Ack timer is always set to a value lesser
 // than the retransmission timer's minimum value (MinRTO). We want the
@@ skipping 158 matching lines @@
   // Set up a pacing sender with a 1 millisecond alarm granularity, the same as
   // the default granularity of the Linux kernel's FQ qdisc.
   using_pacing_ = true;
   send_algorithm_.reset(
       new PacingSender(send_algorithm_.release(),
                        QuicTime::Delta::FromMilliseconds(1),
                        kInitialUnpacedBurst));
 }
 
 }  // namespace net