gfe-relnote: (n/a) Deprecate --gfe2_reloadable_flag_quic_track_ack_height_in_bandwidth_sampler2.
PiperOrigin-RevId: 273343146
Change-Id: I190868992578d41a3ab5764122ac2a15c3ddf723
diff --git a/quic/core/congestion_control/bandwidth_sampler.cc b/quic/core/congestion_control/bandwidth_sampler.cc
index 8899704..1915843 100644
--- a/quic/core/congestion_control/bandwidth_sampler.cc
+++ b/quic/core/congestion_control/bandwidth_sampler.cc
@@ -60,13 +60,7 @@
max_tracked_packets_(GetQuicFlag(FLAGS_quic_max_tracked_packet_count)),
unacked_packet_map_(unacked_packet_map),
max_ack_height_tracker_(max_height_tracker_window_length),
- total_bytes_acked_after_last_ack_event_(0),
- quic_track_ack_height_in_bandwidth_sampler_(
- GetQuicReloadableFlag(quic_track_ack_height_in_bandwidth_sampler2)) {
- if (quic_track_ack_height_in_bandwidth_sampler_) {
- QUIC_RELOADABLE_FLAG_COUNT(quic_track_ack_height_in_bandwidth_sampler2);
- }
-}
+ total_bytes_acked_after_last_ack_event_(0) {}
BandwidthSampler::~BandwidthSampler() {}
diff --git a/quic/core/congestion_control/bandwidth_sampler.h b/quic/core/congestion_control/bandwidth_sampler.h
index 8b279c6..5bbb6ba 100644
--- a/quic/core/congestion_control/bandwidth_sampler.h
+++ b/quic/core/congestion_control/bandwidth_sampler.h
@@ -282,10 +282,6 @@
max_ack_height_tracker_.Reset(new_height, new_time);
}
- bool quic_track_ack_height_in_bandwidth_sampler() const {
- return quic_track_ack_height_in_bandwidth_sampler_;
- }
-
private:
friend class test::BandwidthSamplerPeer;
@@ -399,9 +395,6 @@
MaxAckHeightTracker max_ack_height_tracker_;
QuicByteCount total_bytes_acked_after_last_ack_event_;
-
- // Latched value of --quic_track_ack_height_in_bandwidth_sampler2.
- const bool quic_track_ack_height_in_bandwidth_sampler_;
};
} // namespace quic
diff --git a/quic/core/congestion_control/bbr_sender.cc b/quic/core/congestion_control/bbr_sender.cc
index ae1432a..b0fd50d 100644
--- a/quic/core/congestion_control/bbr_sender.cc
+++ b/quic/core/congestion_control/bbr_sender.cc
@@ -93,9 +93,6 @@
sampler_(unacked_packets, kBandwidthWindowSize),
round_trip_count_(0),
max_bandwidth_(kBandwidthWindowSize, QuicBandwidth::Zero(), 0),
- max_ack_height_(kBandwidthWindowSize, 0, 0),
- aggregation_epoch_start_time_(QuicTime::Zero()),
- aggregation_epoch_bytes_(0),
min_rtt_(QuicTime::Delta::Zero()),
min_rtt_timestamp_(QuicTime::Zero()),
congestion_window_(initial_tcp_congestion_window * kDefaultTCPMSS),
@@ -175,12 +172,6 @@
exiting_quiescence_ = true;
}
- if (!sampler_.quic_track_ack_height_in_bandwidth_sampler()) {
- if (!aggregation_epoch_start_time_.IsInitialized()) {
- aggregation_epoch_start_time_ = sent_time;
- }
- }
-
sampler_.OnPacketSent(sent_time, packet_number, bytes, bytes_in_flight,
is_retransmittable);
}
@@ -287,18 +278,10 @@
startup_rate_reduction_multiplier_ = 2;
}
if (config.HasClientRequestedIndependentOption(kBBR4, perspective)) {
- if (sampler_.quic_track_ack_height_in_bandwidth_sampler()) {
- sampler_.SetMaxAckHeightTrackerWindowLength(2 * kBandwidthWindowSize);
- } else {
- max_ack_height_.SetWindowLength(2 * kBandwidthWindowSize);
- }
+ sampler_.SetMaxAckHeightTrackerWindowLength(2 * kBandwidthWindowSize);
}
if (config.HasClientRequestedIndependentOption(kBBR5, perspective)) {
- if (sampler_.quic_track_ack_height_in_bandwidth_sampler()) {
- sampler_.SetMaxAckHeightTrackerWindowLength(4 * kBandwidthWindowSize);
- } else {
- max_ack_height_.SetWindowLength(4 * kBandwidthWindowSize);
- }
+ sampler_.SetMaxAckHeightTrackerWindowLength(4 * kBandwidthWindowSize);
}
if (GetQuicReloadableFlag(quic_bbr_less_probe_rtt) &&
config.HasClientRequestedIndependentOption(kBBR6, perspective)) {
@@ -413,13 +396,8 @@
UpdateRecoveryState(last_acked_packet, !lost_packets.empty(),
is_round_start);
- const QuicByteCount bytes_acked =
- sampler_.total_bytes_acked() - total_bytes_acked_before;
-
- excess_acked = sampler_.quic_track_ack_height_in_bandwidth_sampler()
- ? sampler_.OnAckEventEnd(max_bandwidth_.GetBest(),
- round_trip_count_)
- : UpdateAckAggregationBytes(event_time, bytes_acked);
+ excess_acked =
+ sampler_.OnAckEventEnd(max_bandwidth_.GetBest(), round_trip_count_);
}
// Handle logic specific to PROBE_BW mode.
@@ -661,11 +639,7 @@
rounds_without_bandwidth_gain_ = 0;
if (expire_ack_aggregation_in_startup_) {
// Expire old excess delivery measurements now that bandwidth increased.
- if (sampler_.quic_track_ack_height_in_bandwidth_sampler()) {
- sampler_.ResetMaxAckHeightTracker(0, round_trip_count_);
- } else {
- max_ack_height_.Reset(0, round_trip_count_);
- }
+ sampler_.ResetMaxAckHeightTracker(0, round_trip_count_);
}
return;
}
@@ -786,31 +760,6 @@
}
}
-// TODO(ianswett): Move this logic into BandwidthSampler.
-QuicByteCount BbrSender::UpdateAckAggregationBytes(
- QuicTime ack_time,
- QuicByteCount newly_acked_bytes) {
- // Compute how many bytes are expected to be delivered, assuming max bandwidth
- // is correct.
- QuicByteCount expected_bytes_acked =
- max_bandwidth_.GetBest() * (ack_time - aggregation_epoch_start_time_);
- // Reset the current aggregation epoch as soon as the ack arrival rate is less
- // than or equal to the max bandwidth.
- if (aggregation_epoch_bytes_ <= expected_bytes_acked) {
- // Reset to start measuring a new aggregation epoch.
- aggregation_epoch_bytes_ = newly_acked_bytes;
- aggregation_epoch_start_time_ = ack_time;
- return 0;
- }
-
- // Compute how many extra bytes were delivered vs max bandwidth.
- // Include the bytes most recently acknowledged to account for stretch acks.
- aggregation_epoch_bytes_ += newly_acked_bytes;
- max_ack_height_.Update(aggregation_epoch_bytes_ - expected_bytes_acked,
- round_trip_count_);
- return aggregation_epoch_bytes_ - expected_bytes_acked;
-}
-
void BbrSender::CalculatePacingRate() {
if (BandwidthEstimate().IsZero()) {
return;
@@ -865,9 +814,7 @@
GetTargetCongestionWindow(congestion_window_gain_);
if (is_at_full_bandwidth_) {
// Add the max recently measured ack aggregation to CWND.
- target_window += sampler_.quic_track_ack_height_in_bandwidth_sampler()
- ? sampler_.max_ack_height()
- : max_ack_height_.GetBest();
+ target_window += sampler_.max_ack_height();
} else if (enable_ack_aggregation_during_startup_) {
// Add the most recent excess acked. Because CWND never decreases in
// STARTUP, this will automatically create a very localized max filter.
diff --git a/quic/core/congestion_control/bbr_sender.h b/quic/core/congestion_control/bbr_sender.h
index 592893e..8321b8c 100644
--- a/quic/core/congestion_control/bbr_sender.h
+++ b/quic/core/congestion_control/bbr_sender.h
@@ -273,13 +273,6 @@
// round-trips.
MaxBandwidthFilter max_bandwidth_;
- // Tracks the maximum number of bytes acked faster than the sending rate.
- MaxAckHeightFilter max_ack_height_;
-
- // The time this aggregation started and the number of bytes acked during it.
- QuicTime aggregation_epoch_start_time_;
- QuicByteCount aggregation_epoch_bytes_;
-
// Minimum RTT estimate. Automatically expires within 10 seconds (and
// triggers PROBE_RTT mode) if no new value is sampled during that period.
QuicTime::Delta min_rtt_;
