Limit QUIC's Cubic CWND increases to 1/2 the bytes acked when in

net/quic/core/congestion_control/cubic.h

 // Copyright (c) 2012 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.
 //
 // Cubic algorithm, helper class to TCP cubic.
 // For details see http://netsrv.csc.ncsu.edu/export/cubic_a_new_tcp_2008.pdf.
 
 #ifndef NET_QUIC_CONGESTION_CONTROL_CUBIC_H_
 #define NET_QUIC_CONGESTION_CONTROL_CUBIC_H_
 
@@ skipping 59 matching lines @@
   QuicTime last_update_time_;
 
   // Last congestion window (in packets) used.
   QuicPacketCount last_congestion_window_;
 
   // Max congestion window (in packets) used just before last loss event.
   // Note: to improve fairness to other streams an additional back off is
   // applied to this value if the new value is below our latest value.
   QuicPacketCount last_max_congestion_window_;
 
+  // Number of acked packets accumulated to increase the CWND via Reno
+  // 'tcp friendly' mode.
+  QuicPacketCount acked_packets_count_;
+
   // Number of acked packets since the cycle started (epoch).
-  QuicPacketCount acked_packets_count_;
+  // Used to limit CWND increases to 1/2 the number of acked packets.
+  QuicPacketCount epoch_packets_count_;
 
   // TCP Reno equivalent congestion window in packets.
   QuicPacketCount estimated_tcp_congestion_window_;
 
   // Origin point of cubic function.
   QuicPacketCount origin_point_congestion_window_;
 
   // Time to origin point of cubic function in 2^10 fractions of a second.
   uint32_t time_to_origin_point_;
 
   // Last congestion window in packets computed by cubic function.
   QuicPacketCount last_target_congestion_window_;
 
   DISALLOW_COPY_AND_ASSIGN(Cubic);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_CONGESTION_CONTROL_CUBIC_H_