Fix QUIC's TCP style retransmission logic to only send a maximum of 2

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 "base/logging.h"
 #include "base/stl_util.h"
 #include "net/quic/congestion_control/pacing_sender.h"
 #include "net/quic/quic_ack_notifier_manager.h"
@@ skipping 26 matching lines @@
 static const int kHistoryPeriodMs = 5000;
 
 static const int kDefaultRetransmissionTimeMs = 500;
 // TCP RFC calls for 1 second RTO however Linux differs from this default and
 // define the minimum RTO to 200ms, we will use the same until we have data to
 // support a higher or lower value.
 static const int kMinRetransmissionTimeMs = 200;
 static const int kMaxRetransmissionTimeMs = 60000;
 static const size_t kMaxRetransmissions = 10;
 
-// We want to make sure if we get a nack packet which triggers several
-// retransmissions, we don't queue up too many packets.  10 is TCP's default
-// initial congestion window(RFC 6928).
-static const size_t kMaxRetransmissionsPerAck = kDefaultInitialWindow;
+// We only retransmit 2 packets per ack.
+static const size_t kMaxRetransmissionsPerAck = 2;
 
 // TCP retransmits after 3 nacks.
 static const size_t kNumberOfNacksBeforeRetransmission = 3;
 
 COMPILE_ASSERT(kHistoryPeriodMs >= kBitrateSmoothingPeriodMs,
                history_must_be_longer_or_equal_to_the_smoothing_period);
 }  // namespace
 
 #define ENDPOINT (is_server_ ? "Server: " : " Client: ")
 
@@ skipping 709 matching lines @@
     return;
   }
 
   using_pacing_ = true;
   send_algorithm_.reset(
       new PacingSender(send_algorithm_.release(),
                        QuicTime::Delta::FromMicroseconds(1)));
 }
 
 }  // namespace net