Add the check for enough loss events into the Bbr2NetworkModel::IsInflightTooHigh() method to simplify the code.
PiperOrigin-RevId: 336470593
Change-Id: I370b79fd09736d508df1996a47dde4b21d453143
diff --git a/quic/core/congestion_control/bbr2_misc.cc b/quic/core/congestion_control/bbr2_misc.cc
index 6053185..9f6744e 100644
--- a/quic/core/congestion_control/bbr2_misc.cc
+++ b/quic/core/congestion_control/bbr2_misc.cc
@@ -243,21 +243,29 @@
}
bool Bbr2NetworkModel::IsInflightTooHigh(
- const Bbr2CongestionEvent& congestion_event) const {
+ const Bbr2CongestionEvent& congestion_event,
+ int64_t max_loss_events) const {
const SendTimeState& send_state = congestion_event.last_packet_send_state;
if (!send_state.is_valid) {
// Not enough information.
return false;
}
+ if (loss_events_in_round() < max_loss_events) {
+ return false;
+ }
+
const QuicByteCount inflight_at_send = BytesInFlight(send_state);
// TODO(wub): Consider total_bytes_lost() - send_state.total_bytes_lost, which
// is the total bytes lost when the largest numbered packet was inflight.
// bytes_lost_in_round_, OTOH, is the total bytes lost in the "current" round.
const QuicByteCount bytes_lost_in_round = bytes_lost_in_round_;
- QUIC_DVLOG(3) << "IsInflightTooHigh: bytes_lost_in_round:"
- << bytes_lost_in_round << ", lost_in_round_threshold:"
+ QUIC_DVLOG(3) << "IsInflightTooHigh: loss_events_in_round:"
+ << loss_events_in_round()
+
+ << " bytes_lost_in_round:" << bytes_lost_in_round
+ << ", lost_in_round_threshold:"
<< inflight_at_send * Params().loss_threshold;
if (inflight_at_send > 0 && bytes_lost_in_round > 0) {
diff --git a/quic/core/congestion_control/bbr2_misc.h b/quic/core/congestion_control/bbr2_misc.h
index f68092b..a6f710a 100644
--- a/quic/core/congestion_control/bbr2_misc.h
+++ b/quic/core/congestion_control/bbr2_misc.h
@@ -394,9 +394,10 @@
bool IsCongestionWindowLimited(
const Bbr2CongestionEvent& congestion_event) const;
- // TODO(wub): Replace this by a new version which takes two thresholds, one
- // is the number of loss events, the other is the percentage of bytes lost.
- bool IsInflightTooHigh(const Bbr2CongestionEvent& congestion_event) const;
+ // Return true if the number of loss events exceeds max_loss_events and
+ // fraction of bytes lost exceed the loss threshold.
+ bool IsInflightTooHigh(const Bbr2CongestionEvent& congestion_event,
+ int64_t max_loss_events) const;
QuicPacketNumber last_sent_packet() const {
return round_trip_counter_.last_sent_packet();
diff --git a/quic/core/congestion_control/bbr2_probe_bw.cc b/quic/core/congestion_control/bbr2_probe_bw.cc
index 1729118..fa72d9f 100644
--- a/quic/core/congestion_control/bbr2_probe_bw.cc
+++ b/quic/core/congestion_control/bbr2_probe_bw.cc
@@ -199,10 +199,8 @@
return NOT_ADAPTED_INVALID_SAMPLE;
}
- const bool has_enough_loss_events =
- model_->loss_events_in_round() >= Params().probe_bw_full_loss_count;
-
- if (has_enough_loss_events && model_->IsInflightTooHigh(congestion_event)) {
+ if (model_->IsInflightTooHigh(congestion_event,
+ Params().probe_bw_full_loss_count)) {
if (cycle_.is_sample_from_probing) {
cycle_.is_sample_from_probing = false;
diff --git a/quic/core/congestion_control/bbr2_startup.cc b/quic/core/congestion_control/bbr2_startup.cc
index 1141ca0..c134765 100644
--- a/quic/core/congestion_control/bbr2_startup.cc
+++ b/quic/core/congestion_control/bbr2_startup.cc
@@ -93,8 +93,6 @@
return;
}
- const int64_t loss_events_in_round = model_->loss_events_in_round();
-
// TODO(wub): In TCP, loss based exit only happens at end of a loss round, in
// QUIC we use the end of the normal round here. It is possible to exit after
// any congestion event, using information of the "rolling round".
@@ -102,19 +100,13 @@
return;
}
- QUIC_DVLOG(3)
- << sender_
- << " CheckExcessiveLosses at end of round. loss_events_in_round:"
- << loss_events_in_round
- << ", threshold:" << Params().startup_full_loss_count << " @ "
- << congestion_event.event_time;
-
// At the end of a round trip. Check if loss is too high in this round.
- if (loss_events_in_round >= Params().startup_full_loss_count &&
- model_->IsInflightTooHigh(congestion_event)) {
+ if (model_->IsInflightTooHigh(congestion_event,
+ Params().startup_full_loss_count)) {
const QuicByteCount bdp = model_->BDP(model_->MaxBandwidth());
QUIC_DVLOG(3) << sender_
<< " Exiting STARTUP due to loss. inflight_hi:" << bdp;
+ // TODO(ianswett): Add a shared method to set inflight_hi in the model.
model_->set_inflight_hi(bdp);
full_bandwidth_reached_ = true;
