| // 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. |
| |
| #ifndef NET_QUIC_QUIC_SENT_PACKET_MANAGER_H_ |
| #define NET_QUIC_QUIC_SENT_PACKET_MANAGER_H_ |
| |
| #include <deque> |
| #include <list> |
| #include <map> |
| #include <queue> |
| #include <set> |
| #include <utility> |
| #include <vector> |
| |
| #include "base/containers/hash_tables.h" |
| #include "net/base/linked_hash_map.h" |
| #include "net/quic/congestion_control/send_algorithm_interface.h" |
| #include "net/quic/quic_ack_notifier_manager.h" |
| #include "net/quic/quic_protocol.h" |
| |
| NET_EXPORT_PRIVATE extern bool FLAGS_track_retransmission_history; |
| NET_EXPORT_PRIVATE extern bool FLAGS_limit_rto_increase_for_tests; |
| NET_EXPORT_PRIVATE extern bool FLAGS_enable_quic_pacing; |
| |
| namespace net { |
| |
| namespace test { |
| class QuicConnectionPeer; |
| class QuicSentPacketManagerPeer; |
| } // namespace test |
| |
| class QuicClock; |
| class QuicConfig; |
| |
| // Class which tracks the set of packets sent on a QUIC connection and contains |
| // a send algorithm to decide when to send new packets. It keeps track of any |
| // retransmittable data associated with each packet. If a packet is |
| // retransmitted, it will keep track of each version of a packet so that if a |
| // previous transmission is acked, the data will not be retransmitted. |
| class NET_EXPORT_PRIVATE QuicSentPacketManager { |
| public: |
| // Struct to store the pending retransmission information. |
| struct PendingRetransmission { |
| PendingRetransmission(QuicPacketSequenceNumber sequence_number, |
| TransmissionType transmission_type, |
| const RetransmittableFrames& retransmittable_frames, |
| QuicSequenceNumberLength sequence_number_length) |
| : sequence_number(sequence_number), |
| transmission_type(transmission_type), |
| retransmittable_frames(retransmittable_frames), |
| sequence_number_length(sequence_number_length) { |
| } |
| |
| QuicPacketSequenceNumber sequence_number; |
| TransmissionType transmission_type; |
| const RetransmittableFrames& retransmittable_frames; |
| QuicSequenceNumberLength sequence_number_length; |
| }; |
| |
| // Interface which provides callbacks that the manager needs. |
| class NET_EXPORT_PRIVATE HelperInterface { |
| public: |
| virtual ~HelperInterface(); |
| |
| // Called to return the sequence number of the next packet to be sent. |
| virtual QuicPacketSequenceNumber GetNextPacketSequenceNumber() = 0; |
| }; |
| |
| QuicSentPacketManager(bool is_server, |
| HelperInterface* helper, |
| const QuicClock* clock, |
| CongestionFeedbackType congestion_type); |
| virtual ~QuicSentPacketManager(); |
| |
| virtual void SetFromConfig(const QuicConfig& config); |
| |
| virtual void SetMaxPacketSize(QuicByteCount max_packet_size); |
| |
| // Called when a new packet is serialized. If the packet contains |
| // retransmittable data, it will be added to the unacked packet map. |
| void OnSerializedPacket(const SerializedPacket& serialized_packet); |
| |
| // Called when a packet is retransmitted with a new sequence number. |
| // Replaces the old entry in the unacked packet map with the new |
| // sequence number. |
| void OnRetransmittedPacket(QuicPacketSequenceNumber old_sequence_number, |
| QuicPacketSequenceNumber new_sequence_number); |
| |
| // Processes the incoming ack and returns true if the retransmission or ack |
| // alarm should be reset. |
| bool OnIncomingAck(const ReceivedPacketInfo& received_info, |
| QuicTime ack_receive_time); |
| |
| // Discards any information for the packet corresponding to |sequence_number|. |
| // If this packet has been retransmitted, information on those packets |
| // will be discarded as well. |
| void DiscardUnackedPacket(QuicPacketSequenceNumber sequence_number); |
| |
| // Returns true if the non-FEC packet |sequence_number| is unacked. |
| bool IsUnacked(QuicPacketSequenceNumber sequence_number) const; |
| |
| // Requests retransmission of all unacked packets of |retransmission_type|. |
| void RetransmitUnackedPackets(RetransmissionType retransmission_type); |
| |
| // Returns true if the unacked packet |sequence_number| has retransmittable |
| // frames. This will only return false if the packet has been acked, if a |
| // previous transmission of this packet was ACK'd, or if this packet has been |
| // retransmitted as with different sequence number. |
| bool HasRetransmittableFrames(QuicPacketSequenceNumber sequence_number) const; |
| |
| // Returns true if there are pending retransmissions. |
| bool HasPendingRetransmissions() const; |
| |
| // Retrieves the next pending retransmission. |
| PendingRetransmission NextPendingRetransmission(); |
| |
| bool HasUnackedPackets() const; |
| |
| // Returns the number of unacked packets which have retransmittable frames. |
| size_t GetNumRetransmittablePackets() const; |
| |
| // Returns the smallest sequence number of a sent packet which has not been |
| // acked by the peer. Excludes any packets which have been retransmitted |
| // with a new sequence number. If all packets have been acked, returns the |
| // sequence number of the next packet that will be sent. |
| QuicPacketSequenceNumber GetLeastUnackedSentPacket() const; |
| |
| // Returns the set of sequence numbers of all unacked packets. |
| // Test only. |
| SequenceNumberSet GetUnackedPackets() const; |
| |
| // Returns true if |sequence_number| is a previous transmission of packet. |
| bool IsPreviousTransmission(QuicPacketSequenceNumber sequence_number) const; |
| |
| // TODO(ianswett): Combine the congestion control related methods below with |
| // some of the methods above and cleanup the resulting code. |
| // Called when we have received an ack frame from peer. |
| // Returns a set containing all the sequence numbers to be nack retransmitted |
| // as a result of the ack. |
| virtual SequenceNumberSet OnIncomingAckFrame( |
| const ReceivedPacketInfo& received_info, |
| const QuicTime& ack_receive_time); |
| |
| // Called when a congestion feedback frame is received from peer. |
| virtual void OnIncomingQuicCongestionFeedbackFrame( |
| const QuicCongestionFeedbackFrame& frame, |
| const QuicTime& feedback_receive_time); |
| |
| // Called when we have sent bytes to the peer. This informs the manager both |
| // the number of bytes sent and if they were retransmitted. |
| virtual void OnPacketSent(QuicPacketSequenceNumber sequence_number, |
| QuicTime sent_time, |
| QuicByteCount bytes, |
| TransmissionType transmission_type, |
| HasRetransmittableData has_retransmittable_data); |
| |
| // Called when the retransmission timer expires. |
| virtual void OnRetransmissionTimeout(); |
| |
| // Called when a packet is timed out, such as an RTO. Removes the bytes from |
| // the congestion manager, but does not change the congestion window size. |
| virtual void OnPacketAbandoned(QuicPacketSequenceNumber sequence_number); |
| |
| // Calculate the time until we can send the next packet to the wire. |
| // Note 1: When kUnknownWaitTime is returned, there is no need to poll |
| // TimeUntilSend again until we receive an OnIncomingAckFrame event. |
| // Note 2: Send algorithms may or may not use |retransmit| in their |
| // calculations. |
| virtual QuicTime::Delta TimeUntilSend(QuicTime now, |
| TransmissionType transmission_type, |
| HasRetransmittableData retransmittable, |
| IsHandshake handshake); |
| |
| // Returns amount of time for delayed ack timer. |
| const QuicTime::Delta DelayedAckTime(); |
| |
| // Returns the current RTO delay. |
| const QuicTime::Delta GetRetransmissionDelay() const; |
| |
| // Returns the estimated smoothed RTT calculated by the congestion algorithm. |
| const QuicTime::Delta SmoothedRtt() const; |
| |
| // Returns the estimated bandwidth calculated by the congestion algorithm. |
| QuicBandwidth BandwidthEstimate() const; |
| |
| // Returns the size of the current congestion window in bytes. Note, this is |
| // not the *available* window. Some send algorithms may not use a congestion |
| // window and will return 0. |
| QuicByteCount GetCongestionWindow() const; |
| |
| // Enables pacing if it has not already been enabled, and if |
| // FLAGS_enable_quic_pacing is set. |
| void MaybeEnablePacing(); |
| |
| bool using_pacing() const { return using_pacing_; } |
| |
| |
| private: |
| friend class test::QuicConnectionPeer; |
| friend class test::QuicSentPacketManagerPeer; |
| |
| struct TransmissionInfo { |
| TransmissionInfo() |
| : retransmittable_frames(NULL), |
| sequence_number_length(PACKET_1BYTE_SEQUENCE_NUMBER), |
| sent_time(QuicTime::Zero()), |
| previous_transmissions(NULL) { } |
| TransmissionInfo(RetransmittableFrames* retransmittable_frames, |
| QuicSequenceNumberLength sequence_number_length) |
| : retransmittable_frames(retransmittable_frames), |
| sequence_number_length(sequence_number_length), |
| sent_time(QuicTime::Zero()), |
| previous_transmissions(NULL) { |
| } |
| |
| RetransmittableFrames* retransmittable_frames; |
| QuicSequenceNumberLength sequence_number_length; |
| // Zero when the packet is serialized, non-zero once it's sent. |
| QuicTime sent_time; |
| // Stores all previous transmissions if the packet has been retransmitted, |
| // and is NULL otherwise. |
| SequenceNumberSet* previous_transmissions; |
| }; |
| |
| typedef linked_hash_map<QuicPacketSequenceNumber, |
| TransmissionInfo> UnackedPacketMap; |
| typedef linked_hash_map<QuicPacketSequenceNumber, |
| TransmissionType> PendingRetransmissionMap; |
| typedef base::hash_map<QuicPacketSequenceNumber, SequenceNumberSet*> |
| PreviousTransmissionMap; |
| |
| // Process the incoming ack looking for newly ack'd data packets. |
| void HandleAckForSentPackets(const ReceivedPacketInfo& received_info); |
| |
| // Update the RTT if the ack is for the largest acked sequence number. |
| void MaybeUpdateRTT(const ReceivedPacketInfo& received_info, |
| const QuicTime& ack_receive_time); |
| |
| // Marks |sequence_number| as having been seen by the peer. Returns an |
| // iterator to the next remaining unacked packet. |
| UnackedPacketMap::iterator MarkPacketReceivedByPeer( |
| QuicPacketSequenceNumber sequence_number); |
| |
| // Simply removes the entries, if any, from the unacked packet map |
| // and the retransmission map. |
| void DiscardPacket(QuicPacketSequenceNumber sequence_number); |
| |
| // Request that |sequence_number| be retransmitted after the other pending |
| // retransmissions. Returns false if there are no retransmittable frames for |
| // |sequence_number| and true if it will be retransmitted. |
| bool MarkForRetransmission(QuicPacketSequenceNumber sequence_number, |
| TransmissionType transmission_type); |
| |
| // Returns the length of the serialized sequence number for |
| // the packet |sequence_number|. |
| QuicSequenceNumberLength GetSequenceNumberLength( |
| QuicPacketSequenceNumber sequence_number) const; |
| |
| // Clears up to |num_to_clear| previous transmissions in order to make room |
| // in the ack frame for new acks. |
| void ClearPreviousRetransmissions(size_t num_to_clear); |
| |
| void CleanupPacketHistory(); |
| |
| // Newly serialized retransmittable and fec packets are added to this map, |
| // which contains owning pointers to any contained frames. If a packet is |
| // retransmitted, this map will contain entries for both the old and the new |
| // packet. The old packet's retransmittable frames entry will be NULL, while |
| // the new packet's entry will contain the frames to retransmit. |
| // If the old packet is acked before the new packet, then the old entry will |
| // be removed from the map and the new entry's retransmittable frames will be |
| // set to NULL. |
| UnackedPacketMap unacked_packets_; |
| |
| // Pending retransmissions which have not been packetized and sent yet. |
| PendingRetransmissionMap pending_retransmissions_; |
| |
| // Tracks if the connection was created by the server. |
| bool is_server_; |
| |
| HelperInterface* helper_; |
| |
| // An AckNotifier can register to be informed when ACKs have been received for |
| // all packets that a given block of data was sent in. The AckNotifierManager |
| // maintains the currently active notifiers. |
| AckNotifierManager ack_notifier_manager_; |
| |
| const QuicClock* clock_; |
| scoped_ptr<SendAlgorithmInterface> send_algorithm_; |
| // Tracks the send time, size, and nack count of sent packets. Packets are |
| // removed after 5 seconds and they've been removed from pending_packets_. |
| SendAlgorithmInterface::SentPacketsMap packet_history_map_; |
| // Packets that are outstanding and have not been abandoned or lost. |
| SequenceNumberSet pending_packets_; |
| QuicTime::Delta rtt_sample_; // RTT estimate from the most recent ACK. |
| // Number of times the RTO timer has fired in a row without receiving an ack. |
| size_t consecutive_rto_count_; |
| bool using_pacing_; |
| |
| DISALLOW_COPY_AND_ASSIGN(QuicSentPacketManager); |
| }; |
| |
| } // namespace net |
| |
| #endif // NET_QUIC_QUIC_SENT_PACKET_MANAGER_H_ |