| // Copyright 2019 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 "quiche/quic/core/congestion_control/bbr2_probe_rtt.h" |
| |
| #include "quiche/quic/core/congestion_control/bbr2_sender.h" |
| #include "quiche/quic/core/quic_time.h" |
| #include "quiche/quic/platform/api/quic_logging.h" |
| |
| namespace quic { |
| |
| void Bbr2ProbeRttMode::Enter(QuicTime /*now*/, |
| const Bbr2CongestionEvent* /*congestion_event*/) { |
| model_->set_pacing_gain(1.0); |
| model_->set_cwnd_gain(1.0); |
| exit_time_ = QuicTime::Zero(); |
| } |
| |
| Bbr2Mode Bbr2ProbeRttMode::OnCongestionEvent( |
| QuicByteCount /*prior_in_flight*/, QuicTime /*event_time*/, |
| const AckedPacketVector& /*acked_packets*/, |
| const LostPacketVector& /*lost_packets*/, |
| const Bbr2CongestionEvent& congestion_event) { |
| if (exit_time_ == QuicTime::Zero()) { |
| if (congestion_event.bytes_in_flight <= InflightTarget() || |
| congestion_event.bytes_in_flight <= |
| sender_->GetMinimumCongestionWindow()) { |
| exit_time_ = congestion_event.event_time + Params().probe_rtt_duration; |
| QUIC_DVLOG(2) << sender_ << " PROBE_RTT exit time set to " << exit_time_ |
| << ". bytes_inflight:" << congestion_event.bytes_in_flight |
| << ", inflight_target:" << InflightTarget() |
| << ", min_congestion_window:" |
| << sender_->GetMinimumCongestionWindow() << " @ " |
| << congestion_event.event_time; |
| } |
| return Bbr2Mode::PROBE_RTT; |
| } |
| |
| return congestion_event.event_time > exit_time_ ? Bbr2Mode::PROBE_BW |
| : Bbr2Mode::PROBE_RTT; |
| } |
| |
| QuicByteCount Bbr2ProbeRttMode::InflightTarget() const { |
| return model_->BDP(model_->MaxBandwidth(), |
| Params().probe_rtt_inflight_target_bdp_fraction); |
| } |
| |
| Limits<QuicByteCount> Bbr2ProbeRttMode::GetCwndLimits() const { |
| QuicByteCount inflight_upper_bound = |
| std::min(model_->inflight_lo(), model_->inflight_hi_with_headroom()); |
| return NoGreaterThan(std::min(inflight_upper_bound, InflightTarget())); |
| } |
| |
| Bbr2Mode Bbr2ProbeRttMode::OnExitQuiescence( |
| QuicTime now, QuicTime /*quiescence_start_time*/) { |
| if (now > exit_time_) { |
| return Bbr2Mode::PROBE_BW; |
| } |
| return Bbr2Mode::PROBE_RTT; |
| } |
| |
| Bbr2ProbeRttMode::DebugState Bbr2ProbeRttMode::ExportDebugState() const { |
| DebugState s; |
| s.inflight_target = InflightTarget(); |
| s.exit_time = exit_time_; |
| return s; |
| } |
| |
| std::ostream& operator<<(std::ostream& os, |
| const Bbr2ProbeRttMode::DebugState& state) { |
| os << "[PROBE_RTT] inflight_target: " << state.inflight_target << "\n"; |
| os << "[PROBE_RTT] exit_time: " << state.exit_time << "\n"; |
| return os; |
| } |
| |
| const Bbr2Params& Bbr2ProbeRttMode::Params() const { return sender_->Params(); } |
| |
| } // namespace quic |