In AimdRateControl, add trial to use current bitrate as min upper limit

This is to ensure that a bad NetworkState estimate can not decrease BWE
unless an delay BW overuse has been detected.

Bug: webrtc:10489
Change-Id: Ic3a516345999eeba814200c2e295a19b347b2eb6
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/317800
Commit-Queue: Per Kjellander <perkj@webrtc.org>
Reviewed-by: Diep Bui <diepbp@google.com>
Auto-Submit: Per Kjellander <perkj@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#40628}
This commit is contained in:
Per K 2023-08-25 14:18:47 +02:00 committed by WebRTC LUCI CQ
parent 4d25a77fd3
commit b5dedfc856
3 changed files with 38 additions and 2 deletions

View File

@ -83,7 +83,8 @@ AimdRateControl::AimdRateControl(const FieldTrialsView& key_value_config,
initial_backoff_interval_("initial_backoff_interval"),
link_capacity_fix_("link_capacity_fix") {
ParseFieldTrial(
{&disable_estimate_bounded_increase_},
{&disable_estimate_bounded_increase_,
&use_current_estimate_as_min_upper_bound_},
key_value_config.Lookup("WebRTC-Bwe-EstimateBoundedIncrease"));
// E.g
// WebRTC-BweAimdRateControlConfig/initial_backoff_interval:100ms/
@ -350,7 +351,10 @@ void AimdRateControl::ChangeBitrate(const RateControlInput& input,
DataRate AimdRateControl::ClampBitrate(DataRate new_bitrate) const {
if (!disable_estimate_bounded_increase_ && network_estimate_ &&
network_estimate_->link_capacity_upper.IsFinite()) {
DataRate upper_bound = network_estimate_->link_capacity_upper;
DataRate upper_bound =
use_current_estimate_as_min_upper_bound_
? std::max(network_estimate_->link_capacity_upper, current_bitrate_)
: network_estimate_->link_capacity_upper;
new_bitrate = std::min(upper_bound, new_bitrate);
}
if (network_estimate_ && network_estimate_->link_capacity_lower.IsFinite() &&

View File

@ -105,6 +105,8 @@ class AimdRateControl {
const bool no_bitrate_increase_in_alr_;
// If "Disabled", estimated link capacity is not used as upper bound.
FieldTrialFlag disable_estimate_bounded_increase_{"Disabled"};
FieldTrialParameter<bool> use_current_estimate_as_min_upper_bound_{"c_upper",
false};
absl::optional<DataRate> last_decrease_;
FieldTrialOptional<TimeDelta> initial_backoff_interval_;
FieldTrialFlag link_capacity_fix_;

View File

@ -212,6 +212,36 @@ TEST(AimdRateControlTest, SetEstimateUpperLimitedByNetworkEstimate) {
network_estimate.link_capacity_upper);
}
TEST(AimdRateControlTest,
SetEstimateUpperLimitedByCurrentBitrateIfNetworkEstimateIsLow) {
AimdRateControl aimd_rate_control(
ExplicitKeyValueConfig(
"WebRTC-Bwe-EstimateBoundedIncrease/c_upper:true/"),
/*send_side=*/true);
aimd_rate_control.SetEstimate(DataRate::BitsPerSec(500'000), kInitialTime);
ASSERT_EQ(aimd_rate_control.LatestEstimate(), DataRate::BitsPerSec(500'000));
NetworkStateEstimate network_estimate;
network_estimate.link_capacity_upper = DataRate::BitsPerSec(300'000);
aimd_rate_control.SetNetworkStateEstimate(network_estimate);
aimd_rate_control.SetEstimate(DataRate::BitsPerSec(700'000), kInitialTime);
EXPECT_EQ(aimd_rate_control.LatestEstimate(), DataRate::BitsPerSec(500'000));
}
TEST(AimdRateControlTest,
SetEstimateDefaultNotUpperLimitedByCurrentBitrateIfNetworkEstimateIsLow) {
AimdRateControl aimd_rate_control(ExplicitKeyValueConfig(""),
/*send_side=*/true);
aimd_rate_control.SetEstimate(DataRate::BitsPerSec(500'000), kInitialTime);
ASSERT_EQ(aimd_rate_control.LatestEstimate(), DataRate::BitsPerSec(500'000));
NetworkStateEstimate network_estimate;
network_estimate.link_capacity_upper = DataRate::BitsPerSec(300'000);
aimd_rate_control.SetNetworkStateEstimate(network_estimate);
aimd_rate_control.SetEstimate(DataRate::BitsPerSec(700'000), kInitialTime);
EXPECT_EQ(aimd_rate_control.LatestEstimate(), DataRate::BitsPerSec(300'000));
}
TEST(AimdRateControlTest, SetEstimateLowerLimitedByNetworkEstimate) {
AimdRateControl aimd_rate_control(ExplicitKeyValueConfig(""),
/*send_side=*/true);