blob: 6a3c5dd35157e053c866a5aff7d7ee1016fb0ab5 [file] [log] [blame]
// Copyright 2015 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.
#include <algorithm>
#include <map>
#include "quic/core/congestion_control/loss_detection_interface.h"
#include "quic/core/quic_packets.h"
#include "quic/core/quic_time.h"
#include "quic/core/quic_types.h"
#include "quic/core/quic_unacked_packet_map.h"
#include "quic/platform/api/quic_export.h"
namespace quic {
// Class which can be configured to implement's TCP's approach of detecting loss
// when 3 nacks have been received for a packet or with a time threshold.
// Also implements TCP's early retransmit(RFC5827).
class QUIC_EXPORT_PRIVATE GeneralLossAlgorithm : public LossDetectionInterface {
GeneralLossAlgorithm() = default;
GeneralLossAlgorithm(const GeneralLossAlgorithm&) = delete;
GeneralLossAlgorithm& operator=(const GeneralLossAlgorithm&) = delete;
~GeneralLossAlgorithm() override {}
void SetFromConfig(const QuicConfig& /*config*/,
Perspective /*perspective*/) override {}
// Uses |largest_acked| and time to decide when packets are lost.
DetectionStats DetectLosses(const QuicUnackedPacketMap& unacked_packets,
QuicTime time,
const RttStats& rtt_stats,
QuicPacketNumber largest_newly_acked,
const AckedPacketVector& packets_acked,
LostPacketVector* packets_lost) override;
// Returns a non-zero value when the early retransmit timer is active.
QuicTime GetLossTimeout() const override;
// Called to increases time and/or packet threshold.
void SpuriousLossDetected(const QuicUnackedPacketMap& unacked_packets,
const RttStats& rtt_stats,
QuicTime ack_receive_time,
QuicPacketNumber packet_number,
QuicPacketNumber previous_largest_acked) override;
void OnConfigNegotiated() override {
<< "Unexpected call to GeneralLossAlgorithm::OnConfigNegotiated";
void OnMinRttAvailable() override {
<< "Unexpected call to GeneralLossAlgorithm::OnMinRttAvailable";
void OnUserAgentIdKnown() override {
<< "Unexpected call to GeneralLossAlgorithm::OnUserAgentIdKnown";
void OnConnectionClosed() override {
<< "Unexpected call to GeneralLossAlgorithm::OnConnectionClosed";
void OnReorderingDetected() override {
<< "Unexpected call to GeneralLossAlgorithm::OnReorderingDetected";
void Initialize(PacketNumberSpace packet_number_space,
LossDetectionInterface* parent);
void Reset();
QuicPacketCount reordering_threshold() const { return reordering_threshold_; }
int reordering_shift() const { return reordering_shift_; }
void set_reordering_shift(int reordering_shift) {
reordering_shift_ = reordering_shift;
void set_reordering_threshold(QuicPacketCount reordering_threshold) {
reordering_threshold_ = reordering_threshold;
bool use_adaptive_reordering_threshold() const {
return use_adaptive_reordering_threshold_;
void set_use_adaptive_reordering_threshold(bool value) {
use_adaptive_reordering_threshold_ = value;
bool use_adaptive_time_threshold() const {
return use_adaptive_time_threshold_;
void enable_adaptive_time_threshold() { use_adaptive_time_threshold_ = true; }
bool use_packet_threshold_for_runt_packets() const {
return use_packet_threshold_for_runt_packets_;
void disable_packet_threshold_for_runt_packets() {
use_packet_threshold_for_runt_packets_ = false;
LossDetectionInterface* parent_ = nullptr;
QuicTime loss_detection_timeout_ = QuicTime::Zero();
// Fraction of a max(SRTT, latest_rtt) to permit reordering before declaring
// loss. Fraction calculated by shifting max(SRTT, latest_rtt) to the right
// by reordering_shift.
int reordering_shift_ = kDefaultLossDelayShift;
// Reordering threshold for loss detection.
QuicPacketCount reordering_threshold_ = kDefaultPacketReorderingThreshold;
// If true, uses adaptive reordering threshold for loss detection.
bool use_adaptive_reordering_threshold_ = true;
// If true, uses adaptive time threshold for time based loss detection.
bool use_adaptive_time_threshold_ = false;
// If true, uses packet threshold when largest acked is a runt packet.
bool use_packet_threshold_for_runt_packets_ = true;
// The least in flight packet. Loss detection should start from this. Please
// note, least_in_flight_ could be largest packet ever sent + 1.
QuicPacketNumber least_in_flight_{1};
PacketNumberSpace packet_number_space_ = NUM_PACKET_NUMBER_SPACES;
} // namespace quic