| // 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 "quic/core/congestion_control/bbr2_drain.h" |
| |
| #include "quic/core/congestion_control/bbr2_sender.h" |
| #include "quic/platform/api/quic_logging.h" |
| |
| namespace quic { |
| |
| Bbr2Mode Bbr2DrainMode::OnCongestionEvent( |
| QuicByteCount /*prior_in_flight*/, |
| QuicTime /*event_time*/, |
| const AckedPacketVector& /*acked_packets*/, |
| const LostPacketVector& /*lost_packets*/, |
| const Bbr2CongestionEvent& congestion_event) { |
| model_->set_pacing_gain(Params().drain_pacing_gain); |
| |
| // Only STARTUP can transition to DRAIN, both of them use the same cwnd gain. |
| DCHECK_EQ(model_->cwnd_gain(), Params().drain_cwnd_gain); |
| model_->set_cwnd_gain(Params().drain_cwnd_gain); |
| |
| QuicByteCount drain_target = DrainTarget(); |
| if (congestion_event.bytes_in_flight <= drain_target) { |
| QUIC_DVLOG(3) << sender_ << " Exiting DRAIN. bytes_in_flight:" |
| << congestion_event.bytes_in_flight |
| << ", bdp:" << model_->BDP() |
| << ", drain_target:" << drain_target << " @ " |
| << congestion_event.event_time; |
| return Bbr2Mode::PROBE_BW; |
| } |
| |
| QUIC_DVLOG(3) << sender_ << " Staying in DRAIN. bytes_in_flight:" |
| << congestion_event.bytes_in_flight << ", bdp:" << model_->BDP() |
| << ", drain_target:" << drain_target << " @ " |
| << congestion_event.event_time; |
| return Bbr2Mode::DRAIN; |
| } |
| |
| QuicByteCount Bbr2DrainMode::DrainTarget() const { |
| QuicByteCount bdp = model_->BDP(); |
| return std::max<QuicByteCount>(bdp, sender_->GetMinimumCongestionWindow()); |
| } |
| |
| Bbr2DrainMode::DebugState Bbr2DrainMode::ExportDebugState() const { |
| DebugState s; |
| s.drain_target = DrainTarget(); |
| return s; |
| } |
| |
| std::ostream& operator<<(std::ostream& os, |
| const Bbr2DrainMode::DebugState& state) { |
| os << "[DRAIN] drain_target: " << state.drain_target << "\n"; |
| return os; |
| } |
| |
| const Bbr2Params& Bbr2DrainMode::Params() const { |
| return sender_->Params(); |
| } |
| |
| } // namespace quic |