| // Copyright (c) 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. |
| // |
| // A send algorithm which adds pacing on top of an another send algorithm. |
| // It uses the underlying sender's bandwidth estimate to determine the |
| // pacing rate to be used. It also takes into consideration the expected |
| // resolution of the underlying alarm mechanism to ensure that alarms are |
| // not set too aggressively, and to smooth out variations. |
| |
| #ifndef NET_QUIC_CONGESTION_CONTROL_PACING_SENDER_H_ |
| #define NET_QUIC_CONGESTION_CONTROL_PACING_SENDER_H_ |
| |
| #include <map> |
| |
| #include "base/basictypes.h" |
| #include "base/memory/scoped_ptr.h" |
| #include "net/quic/congestion_control/send_algorithm_interface.h" |
| #include "net/quic/quic_bandwidth.h" |
| #include "net/quic/quic_clock.h" |
| #include "net/quic/quic_config.h" |
| #include "net/quic/quic_protocol.h" |
| #include "net/quic/quic_time.h" |
| |
| namespace net { |
| |
| class NET_EXPORT_PRIVATE PacingSender : public SendAlgorithmInterface { |
| public: |
| PacingSender(SendAlgorithmInterface* sender, |
| QuicTime::Delta alarm_granularity); |
| virtual ~PacingSender(); |
| |
| // SendAlgorithmInterface methods. |
| virtual void SetFromConfig(const QuicConfig& config, bool is_server) OVERRIDE; |
| virtual void SetMaxPacketSize(QuicByteCount max_packet_size) OVERRIDE; |
| virtual void OnIncomingQuicCongestionFeedbackFrame( |
| const QuicCongestionFeedbackFrame& feedback, |
| QuicTime feedback_receive_time, |
| const SendAlgorithmInterface::SentPacketsMap& sent_packets) OVERRIDE; |
| virtual void OnPacketAcked(QuicPacketSequenceNumber acked_sequence_number, |
| QuicByteCount acked_bytes, |
| QuicTime::Delta rtt) OVERRIDE; |
| virtual void OnPacketLost(QuicPacketSequenceNumber sequence_number, |
| QuicTime ack_receive_time) OVERRIDE; |
| virtual bool OnPacketSent(QuicTime sent_time, |
| QuicPacketSequenceNumber sequence_number, |
| QuicByteCount bytes, |
| TransmissionType transmission_type, |
| HasRetransmittableData is_retransmittable) OVERRIDE; |
| virtual void OnRetransmissionTimeout() OVERRIDE; |
| virtual void OnPacketAbandoned(QuicPacketSequenceNumber sequence_number, |
| QuicByteCount abandoned_bytes) OVERRIDE; |
| virtual QuicTime::Delta TimeUntilSend( |
| QuicTime now, |
| TransmissionType transmission_type, |
| HasRetransmittableData has_retransmittable_data, |
| IsHandshake handshake) OVERRIDE; |
| virtual QuicBandwidth BandwidthEstimate() const OVERRIDE; |
| virtual QuicTime::Delta SmoothedRtt() const OVERRIDE; |
| virtual QuicTime::Delta RetransmissionDelay() const OVERRIDE; |
| virtual QuicByteCount GetCongestionWindow() const OVERRIDE; |
| |
| private: |
| QuicTime::Delta GetTransferTime(QuicByteCount bytes); |
| |
| scoped_ptr<SendAlgorithmInterface> sender_; // Underlying sender. |
| QuicTime::Delta alarm_granularity_; |
| QuicTime next_packet_send_time_; // When can the next packet be sent. |
| bool was_last_send_delayed_; // True when the last send was delayed. |
| QuicByteCount max_segment_size_; |
| |
| DISALLOW_COPY_AND_ASSIGN(PacingSender); |
| }; |
| |
| } // namespace net |
| |
| #endif // NET_QUIC_CONGESTION_CONTROL_PACING_SENDER_H_ |