Change QUIC's pacer to allow a 10 packet burst when the connection comes

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 23 matching lines @@
 static const size_t kMinHandshakeTimeoutMs = 10;
 
 // Sends up to two tail loss probes before firing an RTO,
 // per draft RFC draft-dukkipati-tcpm-tcp-loss-probe.
 static const size_t kDefaultMaxTailLossProbes = 2;
 static const int64 kMinTailLossProbeTimeoutMs = 10;
 
 // Number of samples before we force a new recent min rtt to be captured.
 static const size_t kNumMinRttSamplesAfterQuiescence = 2;
 
+// Number of unpaced packets to send after quiescence.
+static const size_t kInitialUnpacedBurst = 10;
+
 bool HasCryptoHandshake(const TransmissionInfo& transmission_info) {
   if (transmission_info.retransmittable_frames == NULL) {
     return false;
   }
   return transmission_info.retransmittable_frames->HasCryptoHandshake() ==
       IS_HANDSHAKE;
 }
 
 }  // namespace
 
@@ skipping 747 matching lines @@
   }
 
   if (using_pacing_) {
     return;
   }
 
   // Set up a pacing sender with a 5 millisecond alarm granularity.
   using_pacing_ = true;
   send_algorithm_.reset(
       new PacingSender(send_algorithm_.release(),
-                       QuicTime::Delta::FromMilliseconds(5)));
+                       QuicTime::Delta::FromMilliseconds(5),
+                       kInitialUnpacedBurst));
 }
 
 }  // namespace net