Cleanup of unused field trials and options in SendSideBandwidthEstimation
Bug: webrtc:9883
Change-Id: Icbf4d6cb84da51f800343675f181e41b7cc45a6a
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/154422
Reviewed-by: Niels Moller <nisse@webrtc.org>
Commit-Queue: Sebastian Jansson <srte@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#29306}
diff --git a/modules/congestion_controller/goog_cc/send_side_bandwidth_estimation.cc b/modules/congestion_controller/goog_cc/send_side_bandwidth_estimation.cc
index 15480f1..e03b4a2 100644
--- a/modules/congestion_controller/goog_cc/send_side_bandwidth_estimation.cc
+++ b/modules/congestion_controller/goog_cc/send_side_bandwidth_estimation.cc
@@ -37,8 +37,6 @@
constexpr TimeDelta kRtcEventLogPeriod = TimeDelta::Millis<5000>();
// Expecting that RTCP feedback is sent uniformly within [0.5, 1.5]s intervals.
constexpr TimeDelta kMaxRtcpFeedbackInterval = TimeDelta::Millis<5000>();
-constexpr int kFeedbackTimeoutIntervals = 3;
-constexpr TimeDelta kTimeoutInterval = TimeDelta::Millis<1000>();
constexpr float kDefaultLowLossThreshold = 0.02f;
constexpr float kDefaultHighLossThreshold = 0.1f;
@@ -112,11 +110,15 @@
LinkCapacityTracker::~LinkCapacityTracker() {}
-void LinkCapacityTracker::OnOveruse(DataRate delay_based_bitrate,
- Timestamp at_time) {
- capacity_estimate_bps_ =
- std::min(capacity_estimate_bps_, delay_based_bitrate.bps<double>());
- last_link_capacity_update_ = at_time;
+void LinkCapacityTracker::UpdateDelayBasedEstimate(
+ Timestamp at_time,
+ DataRate delay_based_bitrate) {
+ if (delay_based_bitrate < last_delay_based_estimate_) {
+ capacity_estimate_bps_ =
+ std::min(capacity_estimate_bps_, delay_based_bitrate.bps<double>());
+ last_link_capacity_update_ = at_time;
+ }
+ last_delay_based_estimate_ = delay_based_bitrate;
}
void LinkCapacityTracker::OnStartingRate(DataRate start_rate) {
@@ -124,13 +126,17 @@
capacity_estimate_bps_ = start_rate.bps<double>();
}
-void LinkCapacityTracker::OnRateUpdate(DataRate acknowledged,
+void LinkCapacityTracker::OnRateUpdate(absl::optional<DataRate> acknowledged,
+ DataRate target,
Timestamp at_time) {
- if (acknowledged.bps() > capacity_estimate_bps_) {
+ if (!acknowledged)
+ return;
+ DataRate acknowledged_target = std::min(*acknowledged, target);
+ if (acknowledged_target.bps() > capacity_estimate_bps_) {
TimeDelta delta = at_time - last_link_capacity_update_;
double alpha = delta.IsFinite() ? exp(-(delta / tracking_rate.Get())) : 0;
capacity_estimate_bps_ = alpha * capacity_estimate_bps_ +
- (1 - alpha) * acknowledged.bps<double>();
+ (1 - alpha) * acknowledged_target.bps<double>();
}
last_link_capacity_update_ = at_time;
}
@@ -150,8 +156,6 @@
: rtt_limit_("limit", TimeDelta::PlusInfinity()),
drop_fraction_("fraction", 0.5),
drop_interval_("interval", TimeDelta::ms(300)),
- persist_on_route_change_("persist"),
- safe_timeout_("safe_timeout", true),
bandwidth_floor_("floor", DataRate::kbps(5)),
// By initializing this to plus infinity, we make sure that we never
// trigger rtt backoff unless packet feedback is enabled.
@@ -159,18 +163,10 @@
last_propagation_rtt_(TimeDelta::Zero()),
last_packet_sent_(Timestamp::MinusInfinity()) {
ParseFieldTrial(
- {&rtt_limit_, &drop_fraction_, &drop_interval_, &persist_on_route_change_,
- &safe_timeout_, &bandwidth_floor_},
+ {&rtt_limit_, &drop_fraction_, &drop_interval_, &bandwidth_floor_},
field_trial::FindFullName("WebRTC-Bwe-MaxRttLimit"));
}
-void RttBasedBackoff::OnRouteChange() {
- if (!persist_on_route_change_) {
- last_propagation_rtt_update_ = Timestamp::PlusInfinity();
- last_propagation_rtt_ = TimeDelta::Zero();
- }
-}
-
void RttBasedBackoff::UpdatePropagationRtt(Timestamp at_time,
TimeDelta propagation_rtt) {
last_propagation_rtt_update_ = at_time;
@@ -180,12 +176,10 @@
TimeDelta RttBasedBackoff::CorrectedRtt(Timestamp at_time) const {
TimeDelta time_since_rtt = at_time - last_propagation_rtt_update_;
TimeDelta timeout_correction = time_since_rtt;
- if (safe_timeout_) {
- // Avoid timeout when no packets are being sent.
- TimeDelta time_since_packet_sent = at_time - last_packet_sent_;
- timeout_correction =
- std::max(time_since_rtt - time_since_packet_sent, TimeDelta::Zero());
- }
+ // Avoid timeout when no packets are being sent.
+ TimeDelta time_since_packet_sent = at_time - last_packet_sent_;
+ timeout_correction =
+ std::max(time_since_rtt - time_since_packet_sent, TimeDelta::Zero());
return timeout_correction + last_propagation_rtt_;
}
@@ -202,7 +196,6 @@
has_decreased_since_last_fraction_loss_(false),
last_loss_feedback_(Timestamp::MinusInfinity()),
last_loss_packet_report_(Timestamp::MinusInfinity()),
- last_timeout_(Timestamp::MinusInfinity()),
last_fraction_loss_(0),
last_logged_fraction_loss_(0),
last_round_trip_time_(TimeDelta::Zero()),
@@ -217,8 +210,6 @@
rampup_uma_stats_updated_(kNumUmaRampupMetrics, false),
event_log_(event_log),
last_rtc_event_log_(Timestamp::MinusInfinity()),
- in_timeout_experiment_(
- webrtc::field_trial::IsEnabled("WebRTC-FeedbackTimeout")),
low_loss_threshold_(kDefaultLowLossThreshold),
high_loss_threshold_(kDefaultHighLossThreshold),
bitrate_threshold_(kDefaultBitrateThreshold) {
@@ -249,7 +240,6 @@
has_decreased_since_last_fraction_loss_ = false;
last_loss_feedback_ = Timestamp::MinusInfinity();
last_loss_packet_report_ = Timestamp::MinusInfinity();
- last_timeout_ = Timestamp::MinusInfinity();
last_fraction_loss_ = 0;
last_logged_fraction_loss_ = 0;
last_round_trip_time_ = TimeDelta::Zero();
@@ -262,8 +252,6 @@
uma_update_state_ = kNoUpdate;
uma_rtt_state_ = kNoUpdate;
last_rtc_event_log_ = Timestamp::MinusInfinity();
-
- rtt_backoff_.OnRouteChange();
}
void SendSideBandwidthEstimation::SetBitrates(
@@ -323,10 +311,7 @@
void SendSideBandwidthEstimation::UpdateDelayBasedEstimate(Timestamp at_time,
DataRate bitrate) {
- if (bitrate < delay_based_bitrate_) {
- link_capacity_.OnOveruse(bitrate, at_time);
- }
-
+ link_capacity_.UpdateDelayBasedEstimate(at_time, bitrate);
delay_based_bitrate_ = bitrate;
CapBitrateToThresholds(at_time, current_bitrate_);
}
@@ -474,7 +459,6 @@
}
TimeDelta time_since_loss_packet_report = at_time - last_loss_packet_report_;
- TimeDelta time_since_loss_feedback = at_time - last_loss_feedback_;
if (time_since_loss_packet_report < 1.2 * kMaxRtcpFeedbackInterval) {
// We only care about loss above a given bitrate threshold.
float loss = last_fraction_loss_ / 256.0f;
@@ -521,21 +505,6 @@
}
}
}
- } else if (time_since_loss_feedback >
- kFeedbackTimeoutIntervals * kMaxRtcpFeedbackInterval &&
- (last_timeout_.IsInfinite() ||
- at_time - last_timeout_ > kTimeoutInterval)) {
- if (in_timeout_experiment_) {
- RTC_LOG(LS_WARNING) << "Feedback timed out ("
- << ToString(time_since_loss_feedback)
- << "), reducing bitrate.";
- new_bitrate = new_bitrate * 0.8;
- // Reset accumulators since we've already acted on missing feedback and
- // shouldn't to act again on these old lost packets.
- lost_packets_since_last_loss_update_ = 0;
- expected_packets_since_last_loss_update_ = 0;
- last_timeout_ = at_time;
- }
}
CapBitrateToThresholds(at_time, new_bitrate);
@@ -583,25 +552,9 @@
// inlining of very similar functionality.
const TimeDelta time_since_loss_packet_report =
at_time - last_loss_packet_report_;
- const TimeDelta time_since_loss_feedback = at_time - last_loss_feedback_;
if (time_since_loss_packet_report < 1.2 * kMaxRtcpFeedbackInterval) {
new_bitrate = min_bitrate_history_.front().second * 1.08;
new_bitrate += DataRate::bps(1000);
- } else if (time_since_loss_feedback >
- kFeedbackTimeoutIntervals * kMaxRtcpFeedbackInterval &&
- (last_timeout_.IsInfinite() ||
- at_time - last_timeout_ > kTimeoutInterval)) {
- if (in_timeout_experiment_) {
- RTC_LOG(LS_WARNING) << "Feedback timed out ("
- << ToString(time_since_loss_feedback)
- << "), reducing bitrate.";
- new_bitrate = new_bitrate * 0.8;
- // Reset accumulators since we've already acted on missing feedback and
- // shouldn't to act again on these old lost packets.
- lost_packets_since_last_loss_update_ = 0;
- expected_packets_since_last_loss_update_ = 0;
- last_timeout_ = at_time;
- }
}
return new_bitrate;
}
@@ -645,9 +598,6 @@
}
current_bitrate_ = bitrate;
- if (acknowledged_rate_) {
- link_capacity_.OnRateUpdate(std::min(current_bitrate_, *acknowledged_rate_),
- at_time);
- }
+ link_capacity_.OnRateUpdate(acknowledged_rate_, current_bitrate_, at_time);
}
} // namespace webrtc
diff --git a/modules/congestion_controller/goog_cc/send_side_bandwidth_estimation.h b/modules/congestion_controller/goog_cc/send_side_bandwidth_estimation.h
index d2ab240..8c2538f 100644
--- a/modules/congestion_controller/goog_cc/send_side_bandwidth_estimation.h
+++ b/modules/congestion_controller/goog_cc/send_side_bandwidth_estimation.h
@@ -35,9 +35,13 @@
public:
LinkCapacityTracker();
~LinkCapacityTracker();
- void OnOveruse(DataRate delay_based_bitrate, Timestamp at_time);
+ // Call when a new delay-based estimate is available.
+ void UpdateDelayBasedEstimate(Timestamp at_time,
+ DataRate delay_based_bitrate);
void OnStartingRate(DataRate start_rate);
- void OnRateUpdate(DataRate acknowledged, Timestamp at_time);
+ void OnRateUpdate(absl::optional<DataRate> acknowledged,
+ DataRate target,
+ Timestamp at_time);
void OnRttBackoff(DataRate backoff_rate, Timestamp at_time);
DataRate estimate() const;
@@ -45,21 +49,19 @@
FieldTrialParameter<TimeDelta> tracking_rate;
double capacity_estimate_bps_ = 0;
Timestamp last_link_capacity_update_ = Timestamp::MinusInfinity();
+ DataRate last_delay_based_estimate_ = DataRate::PlusInfinity();
};
class RttBasedBackoff {
public:
RttBasedBackoff();
~RttBasedBackoff();
- void OnRouteChange();
void UpdatePropagationRtt(Timestamp at_time, TimeDelta propagation_rtt);
TimeDelta CorrectedRtt(Timestamp at_time) const;
FieldTrialParameter<TimeDelta> rtt_limit_;
FieldTrialParameter<double> drop_fraction_;
FieldTrialParameter<TimeDelta> drop_interval_;
- FieldTrialFlag persist_on_route_change_;
- FieldTrialParameter<bool> safe_timeout_;
FieldTrialParameter<DataRate> bandwidth_floor_;
public:
@@ -149,7 +151,6 @@
bool has_decreased_since_last_fraction_loss_;
Timestamp last_loss_feedback_;
Timestamp last_loss_packet_report_;
- Timestamp last_timeout_;
uint8_t last_fraction_loss_;
uint8_t last_logged_fraction_loss_;
TimeDelta last_round_trip_time_;
@@ -165,7 +166,6 @@
std::vector<bool> rampup_uma_stats_updated_;
RtcEventLog* event_log_;
Timestamp last_rtc_event_log_;
- bool in_timeout_experiment_;
float low_loss_threshold_;
float high_loss_threshold_;
DataRate bitrate_threshold_;
