| // Copyright 2014 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. |
| |
| #ifndef NET_QUIC_CONGESTION_CONTROL_TIME_LOSS_ALGORITHM_H_ |
| #define NET_QUIC_CONGESTION_CONTROL_TIME_LOSS_ALGORITHM_H_ |
| |
| #include <algorithm> |
| #include <map> |
| |
| #include "base/basictypes.h" |
| #include "net/quic/congestion_control/loss_detection_interface.h" |
| #include "net/quic/quic_protocol.h" |
| #include "net/quic/quic_time.h" |
| #include "net/quic/quic_unacked_packet_map.h" |
| |
| namespace net { |
| |
| // A loss detection algorithm which avoids spurious losses and retransmissions |
| // by waiting 1.25 RTTs after a packet was sent instead of nack count. |
| class NET_EXPORT_PRIVATE TimeLossAlgorithm : public LossDetectionInterface { |
| public: |
| TimeLossAlgorithm(); |
| virtual ~TimeLossAlgorithm() {} |
| |
| virtual LossDetectionType GetLossDetectionType() const OVERRIDE; |
| |
| // Declares pending packets less than the largest observed lost when it has |
| // been 1.25 RTT since they were sent. Packets larger than the largest |
| // observed are retransmitted via TLP. |
| virtual SequenceNumberSet DetectLostPackets( |
| const QuicUnackedPacketMap& unacked_packets, |
| const QuicTime& time, |
| QuicPacketSequenceNumber largest_observed, |
| const RttStats& rtt_stats) OVERRIDE; |
| |
| // Returns the time the next packet will be lost, or zero if there |
| // are no nacked pending packets outstanding. |
| // TODO(ianswett): Ideally the RTT variance and the RTT would be used to |
| // determine the time a packet is considered lost. |
| // TODO(ianswett): Consider using Max(1.25 * srtt, 1.125 * last_rtt). |
| virtual QuicTime GetLossTimeout() const OVERRIDE; |
| |
| private: |
| QuicTime loss_detection_timeout_; |
| |
| DISALLOW_COPY_AND_ASSIGN(TimeLossAlgorithm); |
| }; |
| |
| } // namespace net |
| |
| #endif // NET_QUIC_CONGESTION_CONTROL_TIME_LOSS_ALGORITHM_H_ |