| // 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_THIRD_PARTY_QUIC_CORE_QUIC_SENT_PACKET_MANAGER_H_ |
| #define NET_THIRD_PARTY_QUIC_CORE_QUIC_SENT_PACKET_MANAGER_H_ |
| |
| #include <cstddef> |
| #include <map> |
| #include <memory> |
| #include <set> |
| #include <utility> |
| #include <vector> |
| |
| #include "base/macros.h" |
| #include "net/third_party/quic/core/congestion_control/pacing_sender.h" |
| #include "net/third_party/quic/core/congestion_control/rtt_stats.h" |
| #include "net/third_party/quic/core/congestion_control/send_algorithm_interface.h" |
| #include "net/third_party/quic/core/congestion_control/uber_loss_algorithm.h" |
| #include "net/third_party/quic/core/proto/cached_network_parameters.pb.h" |
| #include "net/third_party/quic/core/quic_packets.h" |
| #include "net/third_party/quic/core/quic_pending_retransmission.h" |
| #include "net/third_party/quic/core/quic_sustained_bandwidth_recorder.h" |
| #include "net/third_party/quic/core/quic_transmission_info.h" |
| #include "net/third_party/quic/core/quic_types.h" |
| #include "net/third_party/quic/core/quic_unacked_packet_map.h" |
| #include "net/third_party/quic/platform/api/quic_containers.h" |
| #include "net/third_party/quic/platform/api/quic_export.h" |
| #include "net/third_party/quic/platform/api/quic_string.h" |
| |
| namespace quic { |
| |
| namespace test { |
| class QuicConnectionPeer; |
| class QuicSentPacketManagerPeer; |
| } // namespace test |
| |
| class QuicClock; |
| class QuicConfig; |
| struct QuicConnectionStats; |
| |
| // 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 QUIC_EXPORT_PRIVATE QuicSentPacketManager { |
| public: |
| // Interface which gets callbacks from the QuicSentPacketManager at |
| // interesting points. Implementations must not mutate the state of |
| // the packet manager or connection as a result of these callbacks. |
| class QUIC_EXPORT_PRIVATE DebugDelegate { |
| public: |
| virtual ~DebugDelegate() {} |
| |
| // Called when a spurious retransmission is detected. |
| virtual void OnSpuriousPacketRetransmission( |
| TransmissionType /*transmission_type*/, |
| QuicByteCount /*byte_size*/) {} |
| |
| virtual void OnIncomingAck(const QuicAckFrame& /*ack_frame*/, |
| QuicTime /*ack_receive_time*/, |
| QuicPacketNumber /*largest_observed*/, |
| bool /*rtt_updated*/, |
| QuicPacketNumber /*least_unacked_sent_packet*/) { |
| } |
| |
| virtual void OnPacketLoss(QuicPacketNumber /*lost_packet_number*/, |
| TransmissionType /*transmission_type*/, |
| QuicTime /*detection_time*/) {} |
| |
| virtual void OnApplicationLimited() {} |
| |
| virtual void OnAdjustNetworkParameters(QuicBandwidth /*bandwidth*/, |
| QuicTime::Delta /*rtt*/) {} |
| }; |
| |
| // Interface which gets callbacks from the QuicSentPacketManager when |
| // network-related state changes. Implementations must not mutate the |
| // state of the packet manager as a result of these callbacks. |
| class QUIC_EXPORT_PRIVATE NetworkChangeVisitor { |
| public: |
| virtual ~NetworkChangeVisitor() {} |
| |
| // Called when congestion window or RTT may have changed. |
| virtual void OnCongestionChange() = 0; |
| |
| // Called when the Path MTU may have increased. |
| virtual void OnPathMtuIncreased(QuicPacketLength packet_size) = 0; |
| }; |
| |
| QuicSentPacketManager(Perspective perspective, |
| const QuicClock* clock, |
| QuicConnectionStats* stats, |
| CongestionControlType congestion_control_type, |
| LossDetectionType loss_type); |
| QuicSentPacketManager(const QuicSentPacketManager&) = delete; |
| QuicSentPacketManager& operator=(const QuicSentPacketManager&) = delete; |
| virtual ~QuicSentPacketManager(); |
| |
| virtual void SetFromConfig(const QuicConfig& config); |
| |
| // Pass the CachedNetworkParameters to the send algorithm. |
| void ResumeConnectionState( |
| const CachedNetworkParameters& cached_network_params, |
| bool max_bandwidth_resumption); |
| |
| void SetMaxPacingRate(QuicBandwidth max_pacing_rate) { |
| pacing_sender_.set_max_pacing_rate(max_pacing_rate); |
| } |
| |
| QuicBandwidth MaxPacingRate() const { |
| return pacing_sender_.max_pacing_rate(); |
| } |
| |
| // Set handshake_confirmed_ to true and neuter packets in HANDSHAKE packet |
| // number space. |
| void SetHandshakeConfirmed(); |
| |
| // Requests retransmission of all unacked packets of |retransmission_type|. |
| // The behavior of this method depends on the value of |retransmission_type|: |
| // ALL_UNACKED_RETRANSMISSION - All unacked packets will be retransmitted. |
| // This can happen, for example, after a version negotiation packet has been |
| // received and all packets needs to be retransmitted with the new version. |
| // ALL_INITIAL_RETRANSMISSION - Only initially encrypted packets will be |
| // retransmitted. This can happen, for example, when a CHLO has been rejected |
| // and the previously encrypted data needs to be encrypted with a new key. |
| void RetransmitUnackedPackets(TransmissionType retransmission_type); |
| |
| // Notify the sent packet manager of an external network measurement or |
| // prediction for either |bandwidth| or |rtt|; either can be empty. |
| void AdjustNetworkParameters(QuicBandwidth bandwidth, QuicTime::Delta rtt); |
| |
| // Retransmits the oldest pending packet there is still a tail loss probe |
| // pending. Invoked after OnRetransmissionTimeout. |
| bool MaybeRetransmitTailLossProbe(); |
| |
| // Retransmits the oldest pending packet. |
| bool MaybeRetransmitOldestPacket(TransmissionType type); |
| |
| // Removes the retransmittable frames from all unencrypted packets to ensure |
| // they don't get retransmitted. |
| // TODO(fayang): Consider remove this function when deprecating |
| // quic_use_uber_loss_algorithm. |
| void NeuterUnencryptedPackets(); |
| |
| // Returns true if there are pending retransmissions. |
| // Not const because retransmissions may be cancelled before returning. |
| bool HasPendingRetransmissions() const { |
| return !pending_retransmissions_.empty(); |
| } |
| |
| // Retrieves the next pending retransmission. You must ensure that |
| // there are pending retransmissions prior to calling this function. |
| QuicPendingRetransmission NextPendingRetransmission(); |
| |
| // Returns true if there's outstanding crypto data. |
| bool HasUnackedCryptoPackets() const { |
| return unacked_packets_.HasPendingCryptoPackets(); |
| } |
| |
| // Returns true if there are packets in flight expecting to be acknowledged. |
| bool HasInFlightPackets() const { |
| return unacked_packets_.HasInFlightPackets(); |
| } |
| |
| // Returns the smallest packet number of a serialized packet which has not |
| // been acked by the peer. |
| QuicPacketNumber GetLeastUnacked() const { |
| return unacked_packets_.GetLeastUnacked(); |
| } |
| |
| // Called when we have sent bytes to the peer. This informs the manager both |
| // the number of bytes sent and if they were retransmitted. Returns true if |
| // the sender should reset the retransmission timer. |
| bool OnPacketSent(SerializedPacket* serialized_packet, |
| QuicPacketNumber original_packet_number, |
| QuicTime sent_time, |
| TransmissionType transmission_type, |
| HasRetransmittableData has_retransmittable_data); |
| |
| // Called when the retransmission timer expires. |
| void OnRetransmissionTimeout(); |
| |
| // 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. |
| QuicTime::Delta TimeUntilSend(QuicTime now) const; |
| |
| // Returns the current delay for the retransmission timer, which may send |
| // either a tail loss probe or do a full RTO. Returns QuicTime::Zero() if |
| // there are no retransmittable packets. |
| const QuicTime GetRetransmissionTime() const; |
| |
| // Returns the current delay for the path degrading timer, which is used to |
| // notify the session that this connection is degrading. |
| const QuicTime::Delta GetPathDegradingDelay() const; |
| |
| const RttStats* GetRttStats() const { return &rtt_stats_; } |
| |
| // Returns the estimated bandwidth calculated by the congestion algorithm. |
| QuicBandwidth BandwidthEstimate() const { |
| return send_algorithm_->BandwidthEstimate(); |
| } |
| |
| const QuicSustainedBandwidthRecorder* SustainedBandwidthRecorder() const { |
| return &sustained_bandwidth_recorder_; |
| } |
| |
| // Returns the size of the current congestion window in number of |
| // kDefaultTCPMSS-sized segments. Note, this is not the *available* window. |
| // Some send algorithms may not use a congestion window and will return 0. |
| QuicPacketCount GetCongestionWindowInTcpMss() const { |
| return send_algorithm_->GetCongestionWindow() / kDefaultTCPMSS; |
| } |
| |
| // Returns the number of packets of length |max_packet_length| which fit in |
| // the current congestion window. More packets may end up in flight if the |
| // congestion window has been recently reduced, of if non-full packets are |
| // sent. |
| QuicPacketCount EstimateMaxPacketsInFlight( |
| QuicByteCount max_packet_length) const { |
| return send_algorithm_->GetCongestionWindow() / max_packet_length; |
| } |
| |
| // Returns the size of the current congestion window size in bytes. |
| QuicByteCount GetCongestionWindowInBytes() const { |
| return send_algorithm_->GetCongestionWindow(); |
| } |
| |
| // Returns the size of the slow start congestion window in nume of 1460 byte |
| // TCP segments, aka ssthresh. Some send algorithms do not define a slow |
| // start threshold and will return 0. |
| QuicPacketCount GetSlowStartThresholdInTcpMss() const { |
| return send_algorithm_->GetSlowStartThreshold() / kDefaultTCPMSS; |
| } |
| |
| // Returns debugging information about the state of the congestion controller. |
| QuicString GetDebugState() const; |
| |
| // Returns the number of bytes that are considered in-flight, i.e. not lost or |
| // acknowledged. |
| QuicByteCount GetBytesInFlight() const { |
| return unacked_packets_.bytes_in_flight(); |
| } |
| |
| // No longer retransmit data for |stream_id|. |
| void CancelRetransmissionsForStream(QuicStreamId stream_id); |
| |
| // Called when peer address changes and the connection migrates. |
| void OnConnectionMigration(AddressChangeType type); |
| |
| // Called when an ack frame is initially parsed. |
| void OnAckFrameStart(QuicPacketNumber largest_acked, |
| QuicTime::Delta ack_delay_time, |
| QuicTime ack_receive_time); |
| |
| // Called when ack range [start, end) is received. Populates packets_acked_ |
| // with newly acked packets. |
| void OnAckRange(QuicPacketNumber start, QuicPacketNumber end); |
| |
| // Called when a timestamp is processed. If it's present in packets_acked_, |
| // the timestamp field is set. Otherwise, the timestamp is ignored. |
| void OnAckTimestamp(QuicPacketNumber packet_number, QuicTime timestamp); |
| |
| // Called when an ack frame is parsed completely. Returns true if a previously |
| // -unacked packet is acked. |
| bool OnAckFrameEnd(QuicTime ack_receive_time); |
| |
| // Called to enable/disable letting session decide what to write. |
| void SetSessionDecideWhatToWrite(bool session_decides_what_to_write) { |
| unacked_packets_.SetSessionDecideWhatToWrite(session_decides_what_to_write); |
| } |
| |
| void SetDebugDelegate(DebugDelegate* debug_delegate); |
| |
| void SetPacingAlarmGranularity(QuicTime::Delta alarm_granularity) { |
| pacing_sender_.set_alarm_granularity(alarm_granularity); |
| } |
| |
| QuicPacketNumber GetLargestObserved() const { |
| return unacked_packets_.largest_acked(); |
| } |
| |
| QuicPacketNumber GetLargestSentPacket() const { |
| return unacked_packets_.largest_sent_packet(); |
| } |
| |
| void SetNetworkChangeVisitor(NetworkChangeVisitor* visitor) { |
| DCHECK(!network_change_visitor_); |
| DCHECK(visitor); |
| network_change_visitor_ = visitor; |
| } |
| |
| bool InSlowStart() const { return send_algorithm_->InSlowStart(); } |
| |
| size_t GetConsecutiveRtoCount() const { return consecutive_rto_count_; } |
| |
| size_t GetConsecutiveTlpCount() const { return consecutive_tlp_count_; } |
| |
| void OnApplicationLimited(); |
| |
| const SendAlgorithmInterface* GetSendAlgorithm() const { |
| return send_algorithm_.get(); |
| } |
| |
| void SetSessionNotifier(SessionNotifierInterface* session_notifier) { |
| unacked_packets_.SetSessionNotifier(session_notifier); |
| } |
| |
| QuicTime GetNextReleaseTime() const; |
| |
| QuicPacketCount initial_congestion_window() const { |
| return initial_congestion_window_; |
| } |
| |
| QuicPacketNumber largest_packet_peer_knows_is_acked() const { |
| return largest_packet_peer_knows_is_acked_; |
| } |
| |
| bool handshake_confirmed() const { return handshake_confirmed_; } |
| |
| bool session_decides_what_to_write() const { |
| return unacked_packets_.session_decides_what_to_write(); |
| } |
| |
| size_t pending_timer_transmission_count() const { |
| return pending_timer_transmission_count_; |
| } |
| |
| QuicTime::Delta delayed_ack_time() const { return delayed_ack_time_; } |
| |
| void set_delayed_ack_time(QuicTime::Delta delayed_ack_time) { |
| // The delayed ack time should never be more than one half the min RTO time. |
| DCHECK_LE(delayed_ack_time, (min_rto_timeout_ * 0.5)); |
| delayed_ack_time_ = delayed_ack_time; |
| } |
| |
| const QuicUnackedPacketMap& unacked_packets() const { |
| return unacked_packets_; |
| } |
| |
| // Sets the send algorithm to the given congestion control type and points the |
| // pacing sender at |send_algorithm_|. Can be called any number of times. |
| void SetSendAlgorithm(CongestionControlType congestion_control_type); |
| |
| // Sets the send algorithm to |send_algorithm| and points the pacing sender at |
| // |send_algorithm_|. Takes ownership of |send_algorithm|. Can be called any |
| // number of times. |
| // Setting the send algorithm once the connection is underway is dangerous. |
| void SetSendAlgorithm(SendAlgorithmInterface* send_algorithm); |
| |
| private: |
| friend class test::QuicConnectionPeer; |
| friend class test::QuicSentPacketManagerPeer; |
| |
| // The retransmission timer is a single timer which switches modes depending |
| // upon connection state. |
| enum RetransmissionTimeoutMode { |
| // A conventional TCP style RTO. |
| RTO_MODE, |
| // A tail loss probe. By default, QUIC sends up to two before RTOing. |
| TLP_MODE, |
| // Retransmission of handshake packets prior to handshake completion. |
| HANDSHAKE_MODE, |
| // Re-invoke the loss detection when a packet is not acked before the |
| // loss detection algorithm expects. |
| LOSS_MODE, |
| }; |
| |
| typedef QuicLinkedHashMap<QuicPacketNumber, |
| TransmissionType, |
| QuicPacketNumberHash> |
| PendingRetransmissionMap; |
| |
| // Returns the current retransmission mode. |
| RetransmissionTimeoutMode GetRetransmissionMode() const; |
| |
| // Retransmits all crypto stream packets. |
| void RetransmitCryptoPackets(); |
| |
| // Retransmits two packets for an RTO and removes any non-retransmittable |
| // packets from flight. |
| void RetransmitRtoPackets(); |
| |
| // Returns the timeout for retransmitting crypto handshake packets. |
| const QuicTime::Delta GetCryptoRetransmissionDelay() const; |
| |
| // Returns the timeout for a new tail loss probe. |consecutive_tlp_count| is |
| // the number of consecutive tail loss probes that have already been sent. |
| const QuicTime::Delta GetTailLossProbeDelay( |
| size_t consecutive_tlp_count) const; |
| |
| // Calls GetTailLossProbeDelay() with values from the current state of this |
| // packet manager as its params. |
| const QuicTime::Delta GetTailLossProbeDelay() const { |
| return GetTailLossProbeDelay(consecutive_tlp_count_); |
| } |
| |
| // Returns the retransmission timeout, after which a full RTO occurs. |
| // |consecutive_rto_count| is the number of consecutive RTOs that have already |
| // occurred. |
| const QuicTime::Delta GetRetransmissionDelay( |
| size_t consecutive_rto_count) const; |
| |
| // Calls GetRetransmissionDelay() with values from the current state of this |
| // packet manager as its params. |
| const QuicTime::Delta GetRetransmissionDelay() const { |
| return GetRetransmissionDelay(consecutive_rto_count_); |
| } |
| |
| // Returns the newest transmission associated with a packet. |
| QuicPacketNumber GetNewestRetransmission( |
| QuicPacketNumber packet_number, |
| const QuicTransmissionInfo& transmission_info) const; |
| |
| // Update the RTT if the ack is for the largest acked packet number. |
| // Returns true if the rtt was updated. |
| bool MaybeUpdateRTT(QuicPacketNumber largest_acked, |
| QuicTime::Delta ack_delay_time, |
| QuicTime ack_receive_time); |
| |
| // Invokes the loss detection algorithm and loses and retransmits packets if |
| // necessary. |
| void InvokeLossDetection(QuicTime time); |
| |
| // Invokes OnCongestionEvent if |rtt_updated| is true, there are pending acks, |
| // or pending losses. Clears pending acks and pending losses afterwards. |
| // |prior_in_flight| is the number of bytes in flight before the losses or |
| // acks, |event_time| is normally the timestamp of the ack packet which caused |
| // the event, although it can be the time at which loss detection was |
| // triggered. |
| void MaybeInvokeCongestionEvent(bool rtt_updated, |
| QuicByteCount prior_in_flight, |
| QuicTime event_time); |
| |
| // Removes the retransmittability and in flight properties from the packet at |
| // |info| due to receipt by the peer. |
| void MarkPacketHandled(QuicPacketNumber packet_number, |
| QuicTransmissionInfo* info, |
| QuicTime::Delta ack_delay_time); |
| |
| // Request that |packet_number| be retransmitted after the other pending |
| // retransmissions. Does not add it to the retransmissions if it's already |
| // a pending retransmission. |
| void MarkForRetransmission(QuicPacketNumber packet_number, |
| TransmissionType transmission_type); |
| |
| // Performs whatever work is need to retransmit the data correctly, either |
| // by retransmitting the frames directly or by notifying that the frames |
| // are lost. |
| void HandleRetransmission(TransmissionType transmission_type, |
| QuicTransmissionInfo* transmission_info); |
| |
| // Called after packets have been marked handled with last received ack frame. |
| void PostProcessAfterMarkingPacketHandled( |
| const QuicAckFrame& ack_frame, |
| QuicTime ack_receive_time, |
| bool rtt_updated, |
| QuicByteCount prior_bytes_in_flight); |
| |
| // Notify observers that packet with QuicTransmissionInfo |info| is a spurious |
| // retransmission. It is caller's responsibility to guarantee the packet with |
| // QuicTransmissionInfo |info| is a spurious retransmission before calling |
| // this function. |
| void RecordOneSpuriousRetransmission(const QuicTransmissionInfo& info); |
| |
| // Notify observers about spurious retransmits of packet with |
| // QuicTransmissionInfo |info|. |
| void RecordSpuriousRetransmissions(const QuicTransmissionInfo& info, |
| QuicPacketNumber acked_packet_number); |
| |
| // Sets the initial RTT of the connection. |
| void SetInitialRtt(QuicTime::Delta rtt); |
| |
| // Called when handshake is confirmed to remove the retransmittable frames |
| // from all packets of HANDSHAKE_DATA packet number space to ensure they don't |
| // get retransmitted and will eventually be removed from unacked packets map. |
| // Only used when quic_use_uber_loss_algorithm is true. Please note, this only |
| // applies to QUIC Crypto and needs to be changed when switches to IETF QUIC |
| // with QUIC TLS. |
| void NeuterHandshakePackets(); |
| |
| // Newly serialized retransmittable 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 nullptr, |
| // 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 nullptr. |
| QuicUnackedPacketMap unacked_packets_; |
| |
| // Pending retransmissions which have not been packetized and sent yet. |
| PendingRetransmissionMap pending_retransmissions_; |
| |
| const QuicClock* clock_; |
| QuicConnectionStats* stats_; |
| |
| DebugDelegate* debug_delegate_; |
| NetworkChangeVisitor* network_change_visitor_; |
| QuicPacketCount initial_congestion_window_; |
| RttStats rtt_stats_; |
| std::unique_ptr<SendAlgorithmInterface> send_algorithm_; |
| // Not owned. Always points to |general_loss_algorithm_| outside of tests. |
| LossDetectionInterface* loss_algorithm_; |
| // TODO(fayang): Remove general_loss_algorithm_ when deprecating |
| // quic_use_uber_loss_algorithm. |
| GeneralLossAlgorithm general_loss_algorithm_; |
| UberLossAlgorithm uber_loss_algorithm_; |
| |
| // Tracks the first RTO packet. If any packet before that packet gets acked, |
| // it indicates the RTO was spurious and should be reversed(F-RTO). |
| QuicPacketNumber first_rto_transmission_; |
| // Number of times the RTO timer has fired in a row without receiving an ack. |
| size_t consecutive_rto_count_; |
| // Number of times the tail loss probe has been sent. |
| size_t consecutive_tlp_count_; |
| // Number of times the crypto handshake has been retransmitted. |
| size_t consecutive_crypto_retransmission_count_; |
| // Number of pending transmissions of TLP, RTO, or crypto packets. |
| size_t pending_timer_transmission_count_; |
| // Maximum number of tail loss probes to send before firing an RTO. |
| size_t max_tail_loss_probes_; |
| // Maximum number of packets to send upon RTO. |
| QuicPacketCount max_rto_packets_; |
| // If true, send the TLP at 0.5 RTT. |
| bool enable_half_rtt_tail_loss_probe_; |
| bool using_pacing_; |
| // If true, use the new RTO with loss based CWND reduction instead of the send |
| // algorithms's OnRetransmissionTimeout to reduce the congestion window. |
| bool use_new_rto_; |
| // If true, use a more conservative handshake retransmission policy. |
| bool conservative_handshake_retransmits_; |
| // The minimum TLP timeout. |
| QuicTime::Delta min_tlp_timeout_; |
| // The minimum RTO. |
| QuicTime::Delta min_rto_timeout_; |
| // Whether to use IETF style TLP that includes the max ack delay. |
| bool ietf_style_tlp_; |
| // IETF style TLP, but with a 2x multiplier instead of 1.5x. |
| bool ietf_style_2x_tlp_; |
| |
| // Vectors packets acked and lost as a result of the last congestion event. |
| AckedPacketVector packets_acked_; |
| LostPacketVector packets_lost_; |
| // Largest newly acknowledged packet. |
| QuicPacketNumber largest_newly_acked_; |
| // Largest packet in bytes ever acknowledged. |
| QuicPacketLength largest_mtu_acked_; |
| |
| // Replaces certain calls to |send_algorithm_| when |using_pacing_| is true. |
| // Calls into |send_algorithm_| for the underlying congestion control. |
| PacingSender pacing_sender_; |
| |
| // Set to true after the crypto handshake has successfully completed. After |
| // this is true we no longer use HANDSHAKE_MODE, and further frames sent on |
| // the crypto stream (i.e. SCUP messages) are treated like normal |
| // retransmittable frames. |
| bool handshake_confirmed_; |
| |
| // Records bandwidth from server to client in normal operation, over periods |
| // of time with no loss events. |
| QuicSustainedBandwidthRecorder sustained_bandwidth_recorder_; |
| |
| // The largest acked value that was sent in an ack, which has then been acked. |
| QuicPacketNumber largest_packet_peer_knows_is_acked_; |
| |
| // The maximum amount of time to wait before sending an acknowledgement. |
| // The recovery code assumes the delayed ack time is the same on both sides. |
| QuicTime::Delta delayed_ack_time_; |
| |
| // Latest received ack frame. |
| QuicAckFrame last_ack_frame_; |
| |
| // Record whether RTT gets updated by last largest acked.. |
| bool rtt_updated_; |
| |
| // A reverse iterator of last_ack_frame_.packets. This is reset in |
| // OnAckRangeStart, and gradually moves in OnAckRange.. |
| PacketNumberQueue::const_reverse_iterator acked_packets_iter_; |
| }; |
| |
| } // namespace quic |
| |
| #endif // NET_THIRD_PARTY_QUIC_CORE_QUIC_SENT_PACKET_MANAGER_H_ |