Move congestion window field trial parsing to new class.
This cl is part of work to move several experiments into a joint
experiment group. Most of them vill be ralted to video, hence the name.
Bug: webrtc:10223
Change-Id: I8767c43abb6aa910ab51710eeb908e0f9df1e296
Reviewed-on: https://webrtc-review.googlesource.com/c/118361
Commit-Queue: Erik Språng <sprang@webrtc.org>
Reviewed-by: Sebastian Jansson <srte@webrtc.org>
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#26346}diff --git a/modules/congestion_controller/BUILD.gn b/modules/congestion_controller/BUILD.gn
index 06b8669..7bd049e 100644
--- a/modules/congestion_controller/BUILD.gn
+++ b/modules/congestion_controller/BUILD.gn
@@ -46,6 +46,7 @@
"../../rtc_base:deprecation",
"../../rtc_base:ptr_util",
"../../rtc_base:rate_limiter",
+ "../../rtc_base/experiments:rate_control_settings",
"../../rtc_base/network:sent_packet",
"../../system_wrappers",
"../../system_wrappers:field_trial",
diff --git a/modules/congestion_controller/goog_cc/BUILD.gn b/modules/congestion_controller/goog_cc/BUILD.gn
index 9de1815..9326f86 100644
--- a/modules/congestion_controller/goog_cc/BUILD.gn
+++ b/modules/congestion_controller/goog_cc/BUILD.gn
@@ -45,6 +45,7 @@
"../../../rtc_base:rtc_base_approved",
"../../../rtc_base/experiments:alr_experiment",
"../../../rtc_base/experiments:field_trial_parser",
+ "../../../rtc_base/experiments:rate_control_settings",
"../../../system_wrappers",
"../../bitrate_controller",
"../../remote_bitrate_estimator",
@@ -77,6 +78,7 @@
"../../../api/units:data_size",
"../../../rtc_base:checks",
"../../../rtc_base:rtc_base_approved",
+ "../../../rtc_base/experiments:rate_control_settings",
"//third_party/abseil-cpp/absl/types:optional",
]
}
diff --git a/modules/congestion_controller/goog_cc/congestion_window_pushback_controller.cc b/modules/congestion_controller/goog_cc/congestion_window_pushback_controller.cc
index 7d83b8c..4e6bed6 100644
--- a/modules/congestion_controller/goog_cc/congestion_window_pushback_controller.cc
+++ b/modules/congestion_controller/goog_cc/congestion_window_pushback_controller.cc
@@ -15,46 +15,18 @@
#include "modules/congestion_controller/goog_cc/congestion_window_pushback_controller.h"
#include "rtc_base/checks.h"
+#include "rtc_base/experiments/rate_control_settings.h"
namespace webrtc {
-namespace {
-
-// When CongestionWindowPushback is enabled, the pacer is oblivious to
-// the congestion window. The relation between outstanding data and
-// the congestion window affects encoder allocations directly.
-// This experiment is build on top of congestion window experiment.
-const char kCongestionPushbackExperiment[] = "WebRTC-CongestionWindowPushback";
-const uint32_t kDefaultMinPushbackTargetBitrateBps = 30000;
-
-bool ReadCongestionWindowPushbackExperimentParameter(
- const WebRtcKeyValueConfig* key_value_config,
- uint32_t* min_pushback_target_bitrate_bps) {
- RTC_DCHECK(min_pushback_target_bitrate_bps);
- std::string experiment_string =
- key_value_config->Lookup(kCongestionPushbackExperiment);
- int parsed_values = sscanf(experiment_string.c_str(), "Enabled-%" PRIu32,
- min_pushback_target_bitrate_bps);
- if (parsed_values == 1) {
- RTC_CHECK_GE(*min_pushback_target_bitrate_bps, 0)
- << "Min pushback target bitrate must be greater than or equal to 0.";
- return true;
- }
- return false;
-}
-
-} // namespace
-
CongestionWindowPushbackController::CongestionWindowPushbackController(
const WebRtcKeyValueConfig* key_value_config)
: add_pacing_(
key_value_config->Lookup("WebRTC-AddPacingToCongestionWindowPushback")
- .find("Enabled") == 0) {
- if (!ReadCongestionWindowPushbackExperimentParameter(
- key_value_config, &min_pushback_target_bitrate_bps_)) {
- min_pushback_target_bitrate_bps_ = kDefaultMinPushbackTargetBitrateBps;
- }
-}
+ .find("Enabled") == 0),
+ min_pushback_target_bitrate_bps_(
+ RateControlSettings::ParseFromKeyValueConfig(key_value_config)
+ .CongestionWindowMinPushbackTargetBitrateBps()) {}
CongestionWindowPushbackController::CongestionWindowPushbackController(
const WebRtcKeyValueConfig* key_value_config,
diff --git a/modules/congestion_controller/goog_cc/congestion_window_pushback_controller.h b/modules/congestion_controller/goog_cc/congestion_window_pushback_controller.h
index 9b64093..edf8bcb 100644
--- a/modules/congestion_controller/goog_cc/congestion_window_pushback_controller.h
+++ b/modules/congestion_controller/goog_cc/congestion_window_pushback_controller.h
@@ -43,7 +43,7 @@
int64_t outstanding_bytes_ = 0;
int64_t pacing_bytes_ = 0;
const bool add_pacing_;
- uint32_t min_pushback_target_bitrate_bps_;
+ const uint32_t min_pushback_target_bitrate_bps_;
double encoding_rate_ratio_ = 1.0;
};
diff --git a/modules/congestion_controller/goog_cc/goog_cc_network_control.cc b/modules/congestion_controller/goog_cc/goog_cc_network_control.cc
index 6fd621f..d7b0565 100644
--- a/modules/congestion_controller/goog_cc/goog_cc_network_control.cc
+++ b/modules/congestion_controller/goog_cc/goog_cc_network_control.cc
@@ -32,15 +32,6 @@
namespace webrtc {
namespace {
-
-const char kCwndExperiment[] = "WebRTC-CwndExperiment";
-// When CongestionWindowPushback is enabled, the pacer is oblivious to
-// the congestion window. The relation between outstanding data and
-// the congestion window affects encoder allocations directly.
-const char kCongestionPushbackExperiment[] = "WebRTC-CongestionWindowPushback";
-
-const int64_t kDefaultAcceptedQueueMs = 250;
-
// From RTCPSender video report interval.
constexpr TimeDelta kLossUpdateInterval = TimeDelta::Millis<1000>();
@@ -51,37 +42,6 @@
// overshoots from the encoder.
const float kDefaultPaceMultiplier = 2.5f;
-std::unique_ptr<CongestionWindowPushbackController>
-MaybeCreateCongestionWindowPushbackController(
- const WebRtcKeyValueConfig* const key_value_config) {
- if (key_value_config->Lookup(kCongestionPushbackExperiment).find("Enabled") ==
- 0 &&
- key_value_config->Lookup(kCwndExperiment).find("Enabled") == 0)
- return absl::make_unique<CongestionWindowPushbackController>(
- key_value_config);
- return nullptr;
-}
-
-bool CwndExperimentEnabled(const WebRtcKeyValueConfig* const key_value_config) {
- std::string experiment_string = key_value_config->Lookup(kCwndExperiment);
- // The experiment is enabled iff the field trial string begins with "Enabled".
- return experiment_string.find("Enabled") == 0;
-}
-bool ReadCwndExperimentParameter(
- const WebRtcKeyValueConfig* const key_value_config,
- int64_t* accepted_queue_ms) {
- RTC_DCHECK(accepted_queue_ms);
- std::string experiment_string = key_value_config->Lookup(kCwndExperiment);
- int parsed_values =
- sscanf(experiment_string.c_str(), "Enabled-%" PRId64, accepted_queue_ms);
- if (parsed_values == 1) {
- RTC_CHECK_GE(*accepted_queue_ms, 0)
- << "Accepted must be greater than or equal to 0.";
- return true;
- }
- return false;
-}
-
// Makes sure that the bitrate and the min, max values are in valid range.
static void ClampBitrates(int64_t* bitrate_bps,
int64_t* min_bitrate_bps,
@@ -140,9 +100,14 @@
fall_back_to_probe_rate_(
key_value_config_->Lookup("WebRTC-Bwe-ProbeRateFallback")
.find("Enabled") == 0),
+ rate_control_experiments_(
+ RateControlSettings::ParseFromKeyValueConfig(key_value_config_)),
probe_controller_(new ProbeController(key_value_config_)),
congestion_window_pushback_controller_(
- MaybeCreateCongestionWindowPushbackController(key_value_config_)),
+ rate_control_experiments_.UseCongestionWindowPushback()
+ ? absl::make_unique<CongestionWindowPushbackController>(
+ key_value_config_)
+ : nullptr),
bandwidth_estimation_(
absl::make_unique<SendSideBandwidthEstimation>(event_log_)),
alr_detector_(absl::make_unique<AlrDetector>()),
@@ -170,21 +135,13 @@
DataRate::Zero())),
max_padding_rate_(config.stream_based_config.max_padding_rate.value_or(
DataRate::Zero())),
- max_total_allocated_bitrate_(DataRate::Zero()),
- in_cwnd_experiment_(CwndExperimentEnabled(key_value_config_)),
- accepted_queue_ms_(kDefaultAcceptedQueueMs) {
+ max_total_allocated_bitrate_(DataRate::Zero()) {
RTC_DCHECK(config.constraints.at_time.IsFinite());
ParseFieldTrial(
{&safe_reset_on_route_change_, &safe_reset_acknowledged_rate_},
key_value_config_->Lookup("WebRTC-Bwe-SafeResetOnRouteChange"));
if (delay_based_bwe_)
delay_based_bwe_->SetMinBitrate(congestion_controller::GetMinBitrate());
- if (in_cwnd_experiment_ &&
- !ReadCwndExperimentParameter(key_value_config_, &accepted_queue_ms_)) {
- RTC_LOG(LS_WARNING) << "Failed to parse parameters for CwndExperiment "
- "from field trial string. Experiment disabled.";
- in_cwnd_experiment_ = false;
- }
}
GoogCcNetworkController::~GoogCcNetworkController() {}
@@ -589,13 +546,15 @@
// No valid RTT could be because send-side BWE isn't used, in which case
// we don't try to limit the outstanding packets.
- if (in_cwnd_experiment_ && max_feedback_rtt.IsFinite()) {
+ if (rate_control_experiments_.UseCongestionWindow() &&
+ max_feedback_rtt.IsFinite()) {
int64_t min_feedback_max_rtt_ms =
*std::min_element(feedback_max_rtts_.begin(), feedback_max_rtts_.end());
const DataSize kMinCwnd = DataSize::bytes(2 * 1500);
- TimeDelta time_window =
- TimeDelta::ms(min_feedback_max_rtt_ms + accepted_queue_ms_);
+ TimeDelta time_window = TimeDelta::ms(
+ min_feedback_max_rtt_ms +
+ rate_control_experiments_.GetCongestionWindowAdditionalTimeMs());
DataSize data_window = last_raw_target_rate_ * time_window;
if (current_data_window_) {
data_window =
diff --git a/modules/congestion_controller/goog_cc/goog_cc_network_control.h b/modules/congestion_controller/goog_cc/goog_cc_network_control.h
index 7d65689..f60d31d 100644
--- a/modules/congestion_controller/goog_cc/goog_cc_network_control.h
+++ b/modules/congestion_controller/goog_cc/goog_cc_network_control.h
@@ -34,6 +34,7 @@
#include "modules/congestion_controller/goog_cc/probe_controller.h"
#include "rtc_base/constructor_magic.h"
#include "rtc_base/experiments/field_trial_parser.h"
+#include "rtc_base/experiments/rate_control_settings.h"
namespace webrtc {
@@ -78,6 +79,7 @@
FieldTrialFlag safe_reset_acknowledged_rate_;
const bool use_stable_bandwidth_estimate_;
const bool fall_back_to_probe_rate_;
+ const RateControlSettings rate_control_experiments_;
const std::unique_ptr<ProbeController> probe_controller_;
const std::unique_ptr<CongestionWindowPushbackController>
@@ -113,8 +115,6 @@
DataRate max_padding_rate_;
DataRate max_total_allocated_bitrate_;
- bool in_cwnd_experiment_;
- int64_t accepted_queue_ms_;
bool previously_in_alr = false;
absl::optional<DataSize> current_data_window_;
diff --git a/modules/congestion_controller/include/send_side_congestion_controller.h b/modules/congestion_controller/include/send_side_congestion_controller.h
index b428eed..545be0e 100644
--- a/modules/congestion_controller/include/send_side_congestion_controller.h
+++ b/modules/congestion_controller/include/send_side_congestion_controller.h
@@ -168,8 +168,7 @@
std::unique_ptr<ProbeBitrateEstimator> probe_bitrate_estimator_
RTC_GUARDED_BY(bwe_lock_);
std::unique_ptr<DelayBasedBwe> delay_based_bwe_ RTC_GUARDED_BY(bwe_lock_);
- bool in_cwnd_experiment_;
- int64_t accepted_queue_ms_;
+ absl::optional<int64_t> cwnd_experiment_parameter_;
bool was_in_alr_;
const bool send_side_bwe_with_overhead_;
size_t transport_overhead_bytes_per_packet_ RTC_GUARDED_BY(bwe_lock_);
diff --git a/modules/congestion_controller/send_side_congestion_controller.cc b/modules/congestion_controller/send_side_congestion_controller.cc
index 8b6d223..ef1e2a1 100644
--- a/modules/congestion_controller/send_side_congestion_controller.cc
+++ b/modules/congestion_controller/send_side_congestion_controller.cc
@@ -28,6 +28,7 @@
#include "modules/congestion_controller/goog_cc/probe_controller.h"
#include "modules/remote_bitrate_estimator/include/bwe_defines.h"
#include "rtc_base/checks.h"
+#include "rtc_base/experiments/rate_control_settings.h"
#include "rtc_base/logging.h"
#include "rtc_base/network/sent_packet.h"
#include "rtc_base/rate_limiter.h"
@@ -36,48 +37,7 @@
namespace webrtc {
namespace {
-const char kCwndExperiment[] = "WebRTC-CwndExperiment";
const char kPacerPushbackExperiment[] = "WebRTC-PacerPushbackExperiment";
-
-// When CongestionWindowPushback is enabled, the pacer is oblivious to
-// the congestion window. The relation between outstanding data and
-// the congestion window affects encoder allocations directly.
-const char kCongestionPushbackExperiment[] = "WebRTC-CongestionWindowPushback";
-
-const int64_t kDefaultAcceptedQueueMs = 250;
-
-bool CwndExperimentEnabled(const WebRtcKeyValueConfig* const key_value_config) {
- std::string experiment_string = key_value_config->Lookup(kCwndExperiment);
- // The experiment is enabled iff the field trial string begins with "Enabled".
- return experiment_string.find("Enabled") == 0;
-}
-
-bool ReadCwndExperimentParameter(
- const WebRtcKeyValueConfig* const key_value_config,
- int64_t* accepted_queue_ms) {
- RTC_DCHECK(accepted_queue_ms);
- std::string experiment_string = key_value_config->Lookup(kCwndExperiment);
- int parsed_values =
- sscanf(experiment_string.c_str(), "Enabled-%" PRId64, accepted_queue_ms);
- if (parsed_values == 1) {
- RTC_CHECK_GE(*accepted_queue_ms, 0)
- << "Accepted must be greater than or equal to 0.";
- return true;
- }
- return false;
-}
-
-std::unique_ptr<CongestionWindowPushbackController>
-MaybeCreateCongestionWindowPushbackController(
- const WebRtcKeyValueConfig* const key_value_config) {
- if (key_value_config->Lookup(kCongestionPushbackExperiment).find("Enabled") ==
- 0 &&
- key_value_config->Lookup(kCwndExperiment).find("Enabled") == 0)
- return absl::make_unique<CongestionWindowPushbackController>(
- key_value_config);
- return nullptr;
-}
-
static const int64_t kRetransmitWindowSizeMs = 500;
// Makes sure that the bitrate and the min, max values are in valid range.
@@ -152,24 +112,25 @@
min_bitrate_bps_(congestion_controller::GetMinBitrateBps()),
probe_bitrate_estimator_(new ProbeBitrateEstimator(event_log_)),
delay_based_bwe_(new DelayBasedBwe(key_value_config_, event_log_)),
- in_cwnd_experiment_(CwndExperimentEnabled(key_value_config_)),
- accepted_queue_ms_(kDefaultAcceptedQueueMs),
was_in_alr_(false),
send_side_bwe_with_overhead_(
key_value_config_->Lookup("WebRTC-SendSideBwe-WithOverhead")
.find("Enabled") == 0),
transport_overhead_bytes_per_packet_(0),
pacer_pushback_experiment_(
- IsPacerPushbackExperimentEnabled(key_value_config_)),
- congestion_window_pushback_controller_(
- MaybeCreateCongestionWindowPushbackController(key_value_config_)) {
- delay_based_bwe_->SetMinBitrate(DataRate::bps(min_bitrate_bps_));
- if (in_cwnd_experiment_ &&
- !ReadCwndExperimentParameter(key_value_config_, &accepted_queue_ms_)) {
- RTC_LOG(LS_WARNING) << "Failed to parse parameters for CwndExperiment "
- "from field trial string. Experiment disabled.";
- in_cwnd_experiment_ = false;
+ IsPacerPushbackExperimentEnabled(key_value_config_)) {
+ RateControlSettings experiment_params =
+ RateControlSettings::ParseFromKeyValueConfig(key_value_config);
+ if (experiment_params.UseCongestionWindow()) {
+ cwnd_experiment_parameter_ =
+ experiment_params.GetCongestionWindowAdditionalTimeMs();
}
+ if (experiment_params.UseCongestionWindowPushback()) {
+ congestion_window_pushback_controller_ =
+ absl::make_unique<CongestionWindowPushbackController>(
+ key_value_config_);
+ }
+ delay_based_bwe_->SetMinBitrate(DataRate::bps(min_bitrate_bps_));
}
DEPRECATED_SendSideCongestionController::
@@ -185,8 +146,7 @@
RTC_CHECK_GE(min_pushback_target_bitrate_bps, 0)
<< "Min pushback target bitrate must be greater than or equal to 0.";
- in_cwnd_experiment_ = true;
- accepted_queue_ms_ = accepted_queue_ms;
+ cwnd_experiment_parameter_ = accepted_queue_ms;
congestion_window_pushback_controller_ =
absl::make_unique<CongestionWindowPushbackController>(
key_value_config_, min_pushback_target_bitrate_bps);
@@ -364,7 +324,7 @@
return;
transport_feedback_adapter_.OnSentPacket(sent_packet.packet_id,
sent_packet.send_time_ms);
- if (in_cwnd_experiment_)
+ if (cwnd_experiment_parameter_)
LimitOutstandingBytes(transport_feedback_adapter_.GetOutstandingBytes());
}
@@ -472,14 +432,14 @@
rtc::CritScope cs(&probe_lock_);
SendProbes(probe_controller_->RequestProbe(clock_->TimeInMilliseconds()));
}
- if (in_cwnd_experiment_) {
+ if (cwnd_experiment_parameter_) {
LimitOutstandingBytes(transport_feedback_adapter_.GetOutstandingBytes());
}
}
void DEPRECATED_SendSideCongestionController::LimitOutstandingBytes(
size_t num_outstanding_bytes) {
- RTC_DCHECK(in_cwnd_experiment_);
+ RTC_DCHECK(cwnd_experiment_parameter_);
rtc::CritScope lock(&network_state_lock_);
absl::optional<int64_t> min_rtt_ms =
transport_feedback_adapter_.GetMinFeedbackLoopRtt();
@@ -489,7 +449,7 @@
return;
const size_t kMinCwndBytes = 2 * 1500;
size_t max_outstanding_bytes =
- std::max<size_t>((*min_rtt_ms + accepted_queue_ms_) *
+ std::max<size_t>((*min_rtt_ms + *cwnd_experiment_parameter_) *
last_reported_bitrate_bps_ / 1000 / 8,
kMinCwndBytes);
if (congestion_window_pushback_controller_) {
diff --git a/rtc_base/experiments/BUILD.gn b/rtc_base/experiments/BUILD.gn
index 4b3f2a9..5c0fee2 100644
--- a/rtc_base/experiments/BUILD.gn
+++ b/rtc_base/experiments/BUILD.gn
@@ -97,6 +97,22 @@
]
}
+rtc_static_library("rate_control_settings") {
+ sources = [
+ "rate_control_settings.cc",
+ "rate_control_settings.h",
+ ]
+ deps = [
+ ":field_trial_parser",
+ "../:rtc_base_approved",
+ "../../api/transport:field_trial_based_config",
+ "../../api/transport:webrtc_key_value_config",
+ "../../system_wrappers:field_trial",
+ "//third_party/abseil-cpp/absl/memory:memory",
+ "//third_party/abseil-cpp/absl/types:optional",
+ ]
+}
+
if (rtc_include_tests) {
rtc_source_set("experiments_unittests") {
testonly = true
diff --git a/rtc_base/experiments/OWNERS b/rtc_base/experiments/OWNERS
index 9c55872..20d5d79 100644
--- a/rtc_base/experiments/OWNERS
+++ b/rtc_base/experiments/OWNERS
@@ -6,3 +6,5 @@
per-file normalize_simulcast_size_experiment*=asapersson@webrtc.org
per-file quality_scaling_experiment*=asapersson@webrtc.org
per-file rtt_mult_experiment*=mhoro@webrtc.org
+per-file rate_control_settings*=sprang@webrtc.org
+per-file rate_control_settings*=srte@webrtc.org
diff --git a/rtc_base/experiments/rate_control_settings.cc b/rtc_base/experiments/rate_control_settings.cc
new file mode 100644
index 0000000..81089b8
--- /dev/null
+++ b/rtc_base/experiments/rate_control_settings.cc
@@ -0,0 +1,114 @@
+/*
+ * Copyright (c) 2019 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "rtc_base/experiments/rate_control_settings.h"
+
+#include <inttypes.h>
+#include <stdio.h>
+
+#include <string>
+
+#include "api/transport/field_trial_based_config.h"
+#include "rtc_base/logging.h"
+#include "rtc_base/numerics/safe_conversions.h"
+
+namespace webrtc {
+
+namespace {
+
+const char* kCongestionWindowFieldTrialName = "WebRTC-CwndExperiment";
+const int kDefaultAcceptedQueueMs = 250;
+
+const char* kCongestionWindowPushbackFieldTrialName =
+ "WebRTC-CongestionWindowPushback";
+const int kDefaultMinPushbackTargetBitrateBps = 30000;
+
+absl::optional<int> MaybeReadCwndExperimentParameter(
+ const WebRtcKeyValueConfig* const key_value_config) {
+ int64_t accepted_queue_ms;
+ std::string experiment_string =
+ key_value_config->Lookup(kCongestionWindowFieldTrialName);
+ int parsed_values =
+ sscanf(experiment_string.c_str(), "Enabled-%" PRId64, &accepted_queue_ms);
+ if (parsed_values == 1) {
+ RTC_CHECK_GE(accepted_queue_ms, 0)
+ << "Accepted must be greater than or equal to 0.";
+ return rtc::checked_cast<int>(accepted_queue_ms);
+ } else if (experiment_string.find("Enabled") == 0) {
+ return kDefaultAcceptedQueueMs;
+ }
+ return absl::nullopt;
+}
+
+absl::optional<int> MaybeReadCongestionWindowPushbackExperimentParameter(
+ const WebRtcKeyValueConfig* const key_value_config) {
+ uint32_t min_pushback_target_bitrate_bps;
+ std::string experiment_string =
+ key_value_config->Lookup(kCongestionWindowPushbackFieldTrialName);
+ int parsed_values = sscanf(experiment_string.c_str(), "Enabled-%" PRIu32,
+ &min_pushback_target_bitrate_bps);
+ if (parsed_values == 1) {
+ RTC_CHECK_GE(min_pushback_target_bitrate_bps, 0)
+ << "Min pushback target bitrate must be greater than or equal to 0.";
+ return rtc::checked_cast<int>(min_pushback_target_bitrate_bps);
+ } else if (experiment_string.find("Enabled") == 0) {
+ return kDefaultMinPushbackTargetBitrateBps;
+ }
+ return absl::nullopt;
+}
+
+} // namespace
+
+RateControlSettings::RateControlSettings(
+ const WebRtcKeyValueConfig* const key_value_config)
+ : congestion_window_("cwnd",
+ MaybeReadCwndExperimentParameter(key_value_config)),
+ congestion_window_pushback_(
+ "cwnd_pushback",
+ MaybeReadCongestionWindowPushbackExperimentParameter(
+ key_value_config)) {
+ ParseFieldTrial({&congestion_window_, &congestion_window_pushback_},
+ key_value_config->Lookup("WebRTC-VideoRateControl"));
+}
+
+RateControlSettings::~RateControlSettings() = default;
+RateControlSettings::RateControlSettings(RateControlSettings&&) = default;
+
+RateControlSettings RateControlSettings::ParseFromFieldTrials() {
+ FieldTrialBasedConfig field_trial_config;
+ return RateControlSettings(&field_trial_config);
+}
+
+RateControlSettings RateControlSettings::ParseFromKeyValueConfig(
+ const WebRtcKeyValueConfig* const key_value_config) {
+ FieldTrialBasedConfig field_trial_config;
+ return RateControlSettings(key_value_config ? key_value_config
+ : &field_trial_config);
+}
+
+bool RateControlSettings::UseCongestionWindow() const {
+ return congestion_window_;
+}
+
+int64_t RateControlSettings::GetCongestionWindowAdditionalTimeMs() const {
+ return congestion_window_.GetOptional().value_or(kDefaultAcceptedQueueMs);
+}
+
+bool RateControlSettings::UseCongestionWindowPushback() const {
+ return congestion_window_ && congestion_window_pushback_;
+}
+
+uint32_t RateControlSettings::CongestionWindowMinPushbackTargetBitrateBps()
+ const {
+ return congestion_window_pushback_.GetOptional().value_or(
+ kDefaultMinPushbackTargetBitrateBps);
+}
+
+} // namespace webrtc
diff --git a/rtc_base/experiments/rate_control_settings.h b/rtc_base/experiments/rate_control_settings.h
new file mode 100644
index 0000000..0afda87
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+/*
+ * Copyright (c) 2019 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef RTC_BASE_EXPERIMENTS_RATE_CONTROL_SETTINGS_H_
+#define RTC_BASE_EXPERIMENTS_RATE_CONTROL_SETTINGS_H_
+
+#include "absl/types/optional.h"
+#include "api/transport/webrtc_key_value_config.h"
+#include "rtc_base/experiments/field_trial_parser.h"
+
+namespace webrtc {
+
+class RateControlSettings final {
+ public:
+ ~RateControlSettings();
+ RateControlSettings(RateControlSettings&&);
+
+ static RateControlSettings ParseFromFieldTrials();
+ static RateControlSettings ParseFromKeyValueConfig(
+ const WebRtcKeyValueConfig* const key_value_config);
+
+ // When CongestionWindowPushback is enabled, the pacer is oblivious to
+ // the congestion window. The relation between outstanding data and
+ // the congestion window affects encoder allocations directly.
+ bool UseCongestionWindow() const;
+ int64_t GetCongestionWindowAdditionalTimeMs() const;
+ bool UseCongestionWindowPushback() const;
+ uint32_t CongestionWindowMinPushbackTargetBitrateBps() const;
+
+ private:
+ explicit RateControlSettings(
+ const WebRtcKeyValueConfig* const key_value_config);
+
+ FieldTrialOptional<int> congestion_window_;
+ FieldTrialOptional<int> congestion_window_pushback_;
+};
+
+} // namespace webrtc
+
+#endif // RTC_BASE_EXPERIMENTS_RATE_CONTROL_SETTINGS_H_