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b6c58559a7
This cl adds a new field trial parameter to WebRTC-Bwe-EstimateBoundedIncrease that allows the delay based estimate to immediately increase to the upper link capacity estimate. Bug: none Change-Id: I875121a41f65cc8e76bb87bbf421731ba6b4551b Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/257142 Reviewed-by: Diep Bui <diepbp@webrtc.org> Commit-Queue: Per Kjellander <perkj@webrtc.org> Cr-Commit-Position: refs/heads/main@{#36392}
484 lines
22 KiB
C++
484 lines
22 KiB
C++
/*
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* Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
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*
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* Use of this source code is governed by a BSD-style license
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* that can be found in the LICENSE file in the root of the source
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* tree. An additional intellectual property rights grant can be found
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* in the file PATENTS. All contributing project authors may
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* be found in the AUTHORS file in the root of the source tree.
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*/
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#include "modules/remote_bitrate_estimator/aimd_rate_control.h"
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#include <memory>
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#include "api/transport/field_trial_based_config.h"
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#include "api/units/data_rate.h"
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#include "system_wrappers/include/clock.h"
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#include "test/field_trial.h"
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#include "test/gtest.h"
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namespace webrtc {
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namespace {
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constexpr int64_t kClockInitialTime = 123456;
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constexpr int kMinBwePeriodMs = 2000;
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constexpr int kDefaultPeriodMs = 3000;
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constexpr int kMaxBwePeriodMs = 50000;
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// After an overuse, we back off to 85% to the received bitrate.
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constexpr double kFractionAfterOveruse = 0.85;
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struct AimdRateControlStates {
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std::unique_ptr<AimdRateControl> aimd_rate_control;
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std::unique_ptr<SimulatedClock> simulated_clock;
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FieldTrialBasedConfig field_trials;
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};
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AimdRateControlStates CreateAimdRateControlStates(bool send_side = false) {
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AimdRateControlStates states;
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states.aimd_rate_control.reset(
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new AimdRateControl(&states.field_trials, send_side));
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states.simulated_clock.reset(new SimulatedClock(kClockInitialTime));
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return states;
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}
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absl::optional<DataRate> OptionalRateFromOptionalBps(
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absl::optional<int> bitrate_bps) {
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if (bitrate_bps) {
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return DataRate::BitsPerSec(*bitrate_bps);
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} else {
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return absl::nullopt;
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}
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}
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void UpdateRateControl(const AimdRateControlStates& states,
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const BandwidthUsage& bandwidth_usage,
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absl::optional<uint32_t> throughput_estimate,
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int64_t now_ms) {
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RateControlInput input(bandwidth_usage,
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OptionalRateFromOptionalBps(throughput_estimate));
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states.aimd_rate_control->Update(&input, Timestamp::Millis(now_ms));
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}
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void SetEstimate(const AimdRateControlStates& states, int bitrate_bps) {
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states.aimd_rate_control->SetEstimate(DataRate::BitsPerSec(bitrate_bps),
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states.simulated_clock->CurrentTime());
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}
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} // namespace
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TEST(AimdRateControlTest, MinNearMaxIncreaseRateOnLowBandwith) {
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auto states = CreateAimdRateControlStates();
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constexpr int kBitrate = 30000;
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SetEstimate(states, kBitrate);
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EXPECT_EQ(4000,
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states.aimd_rate_control->GetNearMaxIncreaseRateBpsPerSecond());
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}
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TEST(AimdRateControlTest, NearMaxIncreaseRateIs5kbpsOn90kbpsAnd200msRtt) {
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auto states = CreateAimdRateControlStates();
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constexpr int kBitrate = 90000;
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SetEstimate(states, kBitrate);
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EXPECT_EQ(5000,
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states.aimd_rate_control->GetNearMaxIncreaseRateBpsPerSecond());
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}
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TEST(AimdRateControlTest, NearMaxIncreaseRateIs5kbpsOn60kbpsAnd100msRtt) {
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auto states = CreateAimdRateControlStates();
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constexpr int kBitrate = 60000;
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SetEstimate(states, kBitrate);
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states.aimd_rate_control->SetRtt(TimeDelta::Millis(100));
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EXPECT_EQ(5000,
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states.aimd_rate_control->GetNearMaxIncreaseRateBpsPerSecond());
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}
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TEST(AimdRateControlTest, GetIncreaseRateAndBandwidthPeriod) {
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// Smoothing experiment disabled
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auto states = CreateAimdRateControlStates();
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constexpr int kBitrate = 300000;
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SetEstimate(states, kBitrate);
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UpdateRateControl(states, BandwidthUsage::kBwOverusing, kBitrate,
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states.simulated_clock->TimeInMilliseconds());
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EXPECT_NEAR(14000,
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states.aimd_rate_control->GetNearMaxIncreaseRateBpsPerSecond(),
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1000);
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EXPECT_EQ(kDefaultPeriodMs,
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states.aimd_rate_control->GetExpectedBandwidthPeriod().ms());
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}
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TEST(AimdRateControlTest, BweLimitedByAckedBitrate) {
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auto states = CreateAimdRateControlStates();
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constexpr int kAckedBitrate = 10000;
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SetEstimate(states, kAckedBitrate);
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while (states.simulated_clock->TimeInMilliseconds() - kClockInitialTime <
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20000) {
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UpdateRateControl(states, BandwidthUsage::kBwNormal, kAckedBitrate,
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states.simulated_clock->TimeInMilliseconds());
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states.simulated_clock->AdvanceTimeMilliseconds(100);
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}
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ASSERT_TRUE(states.aimd_rate_control->ValidEstimate());
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EXPECT_EQ(static_cast<uint32_t>(1.5 * kAckedBitrate + 10000),
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states.aimd_rate_control->LatestEstimate().bps());
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}
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TEST(AimdRateControlTest, BweNotLimitedByDecreasingAckedBitrate) {
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auto states = CreateAimdRateControlStates();
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constexpr int kAckedBitrate = 100000;
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SetEstimate(states, kAckedBitrate);
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while (states.simulated_clock->TimeInMilliseconds() - kClockInitialTime <
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20000) {
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UpdateRateControl(states, BandwidthUsage::kBwNormal, kAckedBitrate,
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states.simulated_clock->TimeInMilliseconds());
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states.simulated_clock->AdvanceTimeMilliseconds(100);
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}
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ASSERT_TRUE(states.aimd_rate_control->ValidEstimate());
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// If the acked bitrate decreases the BWE shouldn't be reduced to 1.5x
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// what's being acked, but also shouldn't get to increase more.
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uint32_t prev_estimate = states.aimd_rate_control->LatestEstimate().bps();
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UpdateRateControl(states, BandwidthUsage::kBwNormal, kAckedBitrate / 2,
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states.simulated_clock->TimeInMilliseconds());
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uint32_t new_estimate = states.aimd_rate_control->LatestEstimate().bps();
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EXPECT_NEAR(new_estimate, static_cast<uint32_t>(1.5 * kAckedBitrate + 10000),
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2000);
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EXPECT_EQ(new_estimate, prev_estimate);
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}
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TEST(AimdRateControlTest, DefaultPeriodUntilFirstOveruse) {
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// Smoothing experiment disabled
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auto states = CreateAimdRateControlStates();
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states.aimd_rate_control->SetStartBitrate(DataRate::KilobitsPerSec(300));
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EXPECT_EQ(kDefaultPeriodMs,
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states.aimd_rate_control->GetExpectedBandwidthPeriod().ms());
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states.simulated_clock->AdvanceTimeMilliseconds(100);
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UpdateRateControl(states, BandwidthUsage::kBwOverusing, 280000,
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states.simulated_clock->TimeInMilliseconds());
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EXPECT_NE(kDefaultPeriodMs,
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states.aimd_rate_control->GetExpectedBandwidthPeriod().ms());
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}
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TEST(AimdRateControlTest, ExpectedPeriodAfter20kbpsDropAnd5kbpsIncrease) {
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auto states = CreateAimdRateControlStates();
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constexpr int kInitialBitrate = 110000;
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SetEstimate(states, kInitialBitrate);
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states.simulated_clock->AdvanceTimeMilliseconds(100);
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// Make the bitrate drop by 20 kbps to get to 90 kbps.
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// The rate increase at 90 kbps should be 5 kbps, so the period should be 4 s.
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constexpr int kAckedBitrate =
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(kInitialBitrate - 20000) / kFractionAfterOveruse;
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UpdateRateControl(states, BandwidthUsage::kBwOverusing, kAckedBitrate,
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states.simulated_clock->TimeInMilliseconds());
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EXPECT_EQ(5000,
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states.aimd_rate_control->GetNearMaxIncreaseRateBpsPerSecond());
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EXPECT_EQ(4000, states.aimd_rate_control->GetExpectedBandwidthPeriod().ms());
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}
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TEST(AimdRateControlTest, BandwidthPeriodIsNotBelowMin) {
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auto states = CreateAimdRateControlStates();
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constexpr int kInitialBitrate = 10000;
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SetEstimate(states, kInitialBitrate);
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states.simulated_clock->AdvanceTimeMilliseconds(100);
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// Make a small (1.5 kbps) bitrate drop to 8.5 kbps.
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UpdateRateControl(states, BandwidthUsage::kBwOverusing, kInitialBitrate - 1,
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states.simulated_clock->TimeInMilliseconds());
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EXPECT_EQ(kMinBwePeriodMs,
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states.aimd_rate_control->GetExpectedBandwidthPeriod().ms());
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}
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TEST(AimdRateControlTest, BandwidthPeriodIsNotAboveMaxNoSmoothingExp) {
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auto states = CreateAimdRateControlStates();
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constexpr int kInitialBitrate = 10010000;
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SetEstimate(states, kInitialBitrate);
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states.simulated_clock->AdvanceTimeMilliseconds(100);
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// Make a large (10 Mbps) bitrate drop to 10 kbps.
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constexpr int kAckedBitrate = 10000 / kFractionAfterOveruse;
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UpdateRateControl(states, BandwidthUsage::kBwOverusing, kAckedBitrate,
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states.simulated_clock->TimeInMilliseconds());
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EXPECT_EQ(kMaxBwePeriodMs,
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states.aimd_rate_control->GetExpectedBandwidthPeriod().ms());
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}
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TEST(AimdRateControlTest, SendingRateBoundedWhenThroughputNotEstimated) {
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auto states = CreateAimdRateControlStates();
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constexpr int kInitialBitrateBps = 123000;
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UpdateRateControl(states, BandwidthUsage::kBwNormal, kInitialBitrateBps,
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states.simulated_clock->TimeInMilliseconds());
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// AimdRateControl sets the initial bit rate to what it receives after
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// five seconds has passed.
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// TODO(bugs.webrtc.org/9379): The comment in the AimdRateControl does not
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// match the constant.
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constexpr int kInitializationTimeMs = 5000;
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states.simulated_clock->AdvanceTimeMilliseconds(kInitializationTimeMs + 1);
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UpdateRateControl(states, BandwidthUsage::kBwNormal, kInitialBitrateBps,
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states.simulated_clock->TimeInMilliseconds());
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for (int i = 0; i < 100; ++i) {
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UpdateRateControl(states, BandwidthUsage::kBwNormal, absl::nullopt,
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states.simulated_clock->TimeInMilliseconds());
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states.simulated_clock->AdvanceTimeMilliseconds(100);
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}
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EXPECT_LE(states.aimd_rate_control->LatestEstimate().bps(),
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kInitialBitrateBps * 1.5 + 10000);
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}
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TEST(AimdRateControlTest, EstimateDoesNotIncreaseInAlr) {
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// When alr is detected, the delay based estimator is not allowed to increase
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// bwe since there will be no feedback from the network if the new estimate
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// is correct.
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test::ScopedFieldTrials override_field_trials(
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"WebRTC-DontIncreaseDelayBasedBweInAlr/Enabled/");
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auto states = CreateAimdRateControlStates(/*send_side=*/true);
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constexpr int kInitialBitrateBps = 123000;
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SetEstimate(states, kInitialBitrateBps);
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states.aimd_rate_control->SetInApplicationLimitedRegion(true);
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UpdateRateControl(states, BandwidthUsage::kBwNormal, kInitialBitrateBps,
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states.simulated_clock->TimeInMilliseconds());
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ASSERT_EQ(states.aimd_rate_control->LatestEstimate().bps(),
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kInitialBitrateBps);
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for (int i = 0; i < 100; ++i) {
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UpdateRateControl(states, BandwidthUsage::kBwNormal, absl::nullopt,
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states.simulated_clock->TimeInMilliseconds());
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states.simulated_clock->AdvanceTimeMilliseconds(100);
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}
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EXPECT_EQ(states.aimd_rate_control->LatestEstimate().bps(),
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kInitialBitrateBps);
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}
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TEST(AimdRateControlTest, SetEstimateIncreaseBweInAlr) {
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test::ScopedFieldTrials override_field_trials(
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"WebRTC-DontIncreaseDelayBasedBweInAlr/Enabled/");
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auto states = CreateAimdRateControlStates(/*send_side=*/true);
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constexpr int kInitialBitrateBps = 123000;
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SetEstimate(states, kInitialBitrateBps);
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states.aimd_rate_control->SetInApplicationLimitedRegion(true);
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ASSERT_EQ(states.aimd_rate_control->LatestEstimate().bps(),
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kInitialBitrateBps);
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SetEstimate(states, 2 * kInitialBitrateBps);
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EXPECT_EQ(states.aimd_rate_control->LatestEstimate().bps(),
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2 * kInitialBitrateBps);
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}
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TEST(AimdRateControlTest, SetEstimateUpperLimitedByNetworkEstimate) {
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auto states = CreateAimdRateControlStates(/*send_side=*/true);
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NetworkStateEstimate network_estimate;
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network_estimate.link_capacity_upper = DataRate::KilobitsPerSec(400);
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states.aimd_rate_control->SetNetworkStateEstimate(network_estimate);
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SetEstimate(states, 500'000);
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EXPECT_EQ(states.aimd_rate_control->LatestEstimate(),
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network_estimate.link_capacity_upper);
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}
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TEST(AimdRateControlTest, SetEstimateLowerLimitedByNetworkEstimate) {
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auto states = CreateAimdRateControlStates(/*send_side=*/true);
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NetworkStateEstimate network_estimate;
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network_estimate.link_capacity_lower = DataRate::KilobitsPerSec(400);
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states.aimd_rate_control->SetNetworkStateEstimate(network_estimate);
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SetEstimate(states, 100'000);
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// 0.85 is default backoff factor. (`beta_`)
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EXPECT_EQ(states.aimd_rate_control->LatestEstimate(),
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network_estimate.link_capacity_lower * 0.85);
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}
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TEST(AimdRateControlTest,
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SetEstimateIgnoredIfLowerThanNetworkEstimateAndCurrent) {
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auto states = CreateAimdRateControlStates(/*send_side=*/true);
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SetEstimate(states, 200'000);
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ASSERT_EQ(states.aimd_rate_control->LatestEstimate().kbps(), 200);
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NetworkStateEstimate network_estimate;
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network_estimate.link_capacity_lower = DataRate::KilobitsPerSec(400);
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states.aimd_rate_control->SetNetworkStateEstimate(network_estimate);
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// Ignore the next SetEstimate, since the estimate is lower than 85% of
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// the network estimate.
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SetEstimate(states, 100'000);
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EXPECT_EQ(states.aimd_rate_control->LatestEstimate().kbps(), 200);
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}
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TEST(AimdRateControlTest, SetEstimateIgnoresNetworkEstimatesLowerThanCurrent) {
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test::ScopedFieldTrials override_field_trials(
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"WebRTC-Bwe-EstimateBoundedIncrease/"
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"ratio:0.85,ignore_acked:true,ignore_decr:true/");
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auto states = CreateAimdRateControlStates(/*send_side=*/true);
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states.aimd_rate_control->SetStartBitrate(DataRate::KilobitsPerSec(30));
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NetworkStateEstimate network_estimate;
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network_estimate.link_capacity_upper = DataRate::KilobitsPerSec(400);
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states.aimd_rate_control->SetNetworkStateEstimate(network_estimate);
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SetEstimate(states, 500'000);
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ASSERT_EQ(states.aimd_rate_control->LatestEstimate(),
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network_estimate.link_capacity_upper * 0.85);
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NetworkStateEstimate lower_network_estimate;
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lower_network_estimate.link_capacity_upper = DataRate::KilobitsPerSec(300);
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states.aimd_rate_control->SetNetworkStateEstimate(lower_network_estimate);
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SetEstimate(states, 500'000);
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EXPECT_EQ(states.aimd_rate_control->LatestEstimate(),
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network_estimate.link_capacity_upper * 0.85);
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}
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TEST(AimdRateControlTest, EstimateIncreaseWhileNotInAlr) {
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// Allow the estimate to increase as long as alr is not detected to ensure
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// tha BWE can not get stuck at a certain bitrate.
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test::ScopedFieldTrials override_field_trials(
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"WebRTC-DontIncreaseDelayBasedBweInAlr/Enabled/");
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auto states = CreateAimdRateControlStates(/*send_side=*/true);
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constexpr int kInitialBitrateBps = 123000;
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SetEstimate(states, kInitialBitrateBps);
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states.aimd_rate_control->SetInApplicationLimitedRegion(false);
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UpdateRateControl(states, BandwidthUsage::kBwNormal, kInitialBitrateBps,
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states.simulated_clock->TimeInMilliseconds());
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for (int i = 0; i < 100; ++i) {
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UpdateRateControl(states, BandwidthUsage::kBwNormal, absl::nullopt,
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states.simulated_clock->TimeInMilliseconds());
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states.simulated_clock->AdvanceTimeMilliseconds(100);
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}
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EXPECT_GT(states.aimd_rate_control->LatestEstimate().bps(),
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kInitialBitrateBps);
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}
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TEST(AimdRateControlTest, EstimateNotLimitedByNetworkEstimateIfDisabled) {
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test::ScopedFieldTrials override_field_trials(
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"WebRTC-Bwe-EstimateBoundedIncrease/Disabled/");
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auto states = CreateAimdRateControlStates(/*send_side=*/true);
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constexpr int kInitialBitrateBps = 123000;
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SetEstimate(states, kInitialBitrateBps);
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states.aimd_rate_control->SetInApplicationLimitedRegion(false);
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NetworkStateEstimate network_estimate;
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network_estimate.link_capacity_upper = DataRate::KilobitsPerSec(150);
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states.aimd_rate_control->SetNetworkStateEstimate(network_estimate);
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for (int i = 0; i < 100; ++i) {
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UpdateRateControl(states, BandwidthUsage::kBwNormal, absl::nullopt,
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states.simulated_clock->TimeInMilliseconds());
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states.simulated_clock->AdvanceTimeMilliseconds(100);
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}
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EXPECT_GT(states.aimd_rate_control->LatestEstimate(),
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network_estimate.link_capacity_upper);
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}
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TEST(AimdRateControlTest,
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EstimateSlowlyIncreaseToUpperLinkCapacityEstimateIfConfigured) {
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// Even if alr is detected, the delay based estimator is allowed to increase
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// up to a percentage of upper link capacity.
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test::ScopedFieldTrials override_field_trials(
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"WebRTC-Bwe-EstimateBoundedIncrease/"
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"ratio:0.85,ignore_acked:true,immediate_incr:false/"
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"WebRTC-DontIncreaseDelayBasedBweInAlr/Enabled/");
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auto states = CreateAimdRateControlStates(/*send_side=*/true);
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constexpr int kInitialBitrateBps = 123000;
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SetEstimate(states, kInitialBitrateBps);
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states.aimd_rate_control->SetInApplicationLimitedRegion(true);
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NetworkStateEstimate network_estimate;
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network_estimate.link_capacity_upper = DataRate::KilobitsPerSec(200);
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states.aimd_rate_control->SetNetworkStateEstimate(network_estimate);
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for (int i = 0; i < 10; ++i) {
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UpdateRateControl(states, BandwidthUsage::kBwNormal, absl::nullopt,
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states.simulated_clock->TimeInMilliseconds());
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states.simulated_clock->AdvanceTimeMilliseconds(100);
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EXPECT_LT(states.aimd_rate_control->LatestEstimate(),
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network_estimate.link_capacity_upper * 0.85);
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}
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for (int i = 0; i < 50; ++i) {
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UpdateRateControl(states, BandwidthUsage::kBwNormal, absl::nullopt,
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states.simulated_clock->TimeInMilliseconds());
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states.simulated_clock->AdvanceTimeMilliseconds(100);
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}
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EXPECT_EQ(states.aimd_rate_control->LatestEstimate(),
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network_estimate.link_capacity_upper * 0.85);
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}
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TEST(AimdRateControlTest,
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EstimateImmediatelyIncreaseToUpperLinkCapacityEstimateIfConfigured) {
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// Even if alr is detected, the delay based estimator is allowed to increase
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// up to a percentage of upper link capacity.
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test::ScopedFieldTrials override_field_trials(
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"WebRTC-Bwe-EstimateBoundedIncrease/"
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"ratio:0.85,ignore_acked:true,immediate_incr:true/"
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"WebRTC-DontIncreaseDelayBasedBweInAlr/Enabled/");
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auto states = CreateAimdRateControlStates(/*send_side=*/true);
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constexpr int kInitialBitrateBps = 123000;
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SetEstimate(states, kInitialBitrateBps);
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states.aimd_rate_control->SetInApplicationLimitedRegion(true);
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|
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NetworkStateEstimate network_estimate;
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network_estimate.link_capacity_upper = DataRate::KilobitsPerSec(200);
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states.aimd_rate_control->SetNetworkStateEstimate(network_estimate);
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UpdateRateControl(states, BandwidthUsage::kBwNormal, absl::nullopt,
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states.simulated_clock->TimeInMilliseconds());
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EXPECT_EQ(states.aimd_rate_control->LatestEstimate(),
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|
network_estimate.link_capacity_upper * 0.85);
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}
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|
|
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TEST(AimdRateControlTest, EstimateNotLoweredByNetworkEstimate) {
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// The delay based estimator is allowed to increase up to a percentage of
|
|
// upper link capacity but does not decrease unless the delay detector
|
|
// discover an overuse.
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test::ScopedFieldTrials override_field_trials(
|
|
"WebRTC-Bwe-EstimateBoundedIncrease/"
|
|
"ratio:0.85,ignore_acked:true,ignore_decr:true/"
|
|
"WebRTC-DontIncreaseDelayBasedBweInAlr/Enabled/");
|
|
auto states = CreateAimdRateControlStates(/*send_side=*/true);
|
|
constexpr int kInitialBitrateBps = 123000;
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|
constexpr int kEstimatedThroughputBps = 30'000;
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|
SetEstimate(states, kInitialBitrateBps);
|
|
|
|
NetworkStateEstimate network_estimate;
|
|
network_estimate.link_capacity_upper = DataRate::KilobitsPerSec(200);
|
|
states.aimd_rate_control->SetNetworkStateEstimate(network_estimate);
|
|
for (int i = 0; i < 100; ++i) {
|
|
UpdateRateControl(states, BandwidthUsage::kBwNormal,
|
|
kEstimatedThroughputBps,
|
|
states.simulated_clock->TimeInMilliseconds());
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|
states.simulated_clock->AdvanceTimeMilliseconds(100);
|
|
}
|
|
DataRate estimate_after_increase = states.aimd_rate_control->LatestEstimate();
|
|
ASSERT_EQ(estimate_after_increase,
|
|
network_estimate.link_capacity_upper * 0.85);
|
|
|
|
// A lower network estimate does not decrease the estimate immediately,
|
|
// but the estimate is not allowed to increase.
|
|
network_estimate.link_capacity_upper = DataRate::KilobitsPerSec(100);
|
|
network_estimate.link_capacity_lower = DataRate::KilobitsPerSec(80);
|
|
states.aimd_rate_control->SetNetworkStateEstimate(network_estimate);
|
|
for (int i = 0; i < 10; ++i) {
|
|
UpdateRateControl(states, BandwidthUsage::kBwNormal,
|
|
kEstimatedThroughputBps,
|
|
states.simulated_clock->TimeInMilliseconds());
|
|
states.simulated_clock->AdvanceTimeMilliseconds(100);
|
|
EXPECT_EQ(states.aimd_rate_control->LatestEstimate(),
|
|
estimate_after_increase);
|
|
}
|
|
|
|
// If the detector detects and overuse, BWE drops to a value relative the
|
|
// network estimate.
|
|
UpdateRateControl(states, BandwidthUsage::kBwOverusing,
|
|
kEstimatedThroughputBps,
|
|
states.simulated_clock->TimeInMilliseconds());
|
|
EXPECT_LT(states.aimd_rate_control->LatestEstimate(),
|
|
network_estimate.link_capacity_lower);
|
|
EXPECT_GT(states.aimd_rate_control->LatestEstimate().bps(),
|
|
kEstimatedThroughputBps);
|
|
}
|
|
|
|
TEST(AimdRateControlTest, EstimateDoesNotIncreaseInAlrIfNetworkEstimateNotSet) {
|
|
// When alr is detected, the delay based estimator is not allowed to increase
|
|
// bwe since there will be no feedback from the network if the new estimate
|
|
// is correct.
|
|
test::ScopedFieldTrials override_field_trials(
|
|
"WebRTC-Bwe-EstimateBoundedIncrease/ratio:0.85,ignore_acked:true/"
|
|
"WebRTC-DontIncreaseDelayBasedBweInAlr/Enabled/");
|
|
auto states = CreateAimdRateControlStates(/*send_side=*/true);
|
|
constexpr int kInitialBitrateBps = 123000;
|
|
SetEstimate(states, kInitialBitrateBps);
|
|
states.aimd_rate_control->SetInApplicationLimitedRegion(true);
|
|
UpdateRateControl(states, BandwidthUsage::kBwNormal, kInitialBitrateBps,
|
|
states.simulated_clock->TimeInMilliseconds());
|
|
ASSERT_EQ(states.aimd_rate_control->LatestEstimate().bps(),
|
|
kInitialBitrateBps);
|
|
|
|
for (int i = 0; i < 100; ++i) {
|
|
UpdateRateControl(states, BandwidthUsage::kBwNormal, absl::nullopt,
|
|
states.simulated_clock->TimeInMilliseconds());
|
|
states.simulated_clock->AdvanceTimeMilliseconds(100);
|
|
}
|
|
EXPECT_EQ(states.aimd_rate_control->LatestEstimate().bps(),
|
|
kInitialBitrateBps);
|
|
}
|
|
|
|
} // namespace webrtc
|