/* * Copyright (c) 2012 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 "call/bitrate_allocator.h" #include #include #include #include "absl/strings/string_view.h" #include "system_wrappers/include/clock.h" #include "test/gmock.h" #include "test/gtest.h" using ::testing::_; using ::testing::AllOf; using ::testing::Field; using ::testing::NiceMock; namespace webrtc { namespace { auto AllocationLimitsEq(uint32_t min_allocatable_rate_bps, uint32_t max_padding_rate_bps, uint32_t max_allocatable_rate_bps) { return AllOf(Field(&BitrateAllocationLimits::min_allocatable_rate, DataRate::BitsPerSec(min_allocatable_rate_bps)), Field(&BitrateAllocationLimits::max_allocatable_rate, DataRate::BitsPerSec(max_allocatable_rate_bps)), Field(&BitrateAllocationLimits::max_padding_rate, DataRate::BitsPerSec(max_padding_rate_bps))); } auto AllocationLimitsEq(uint32_t min_allocatable_rate_bps, uint32_t max_padding_rate_bps) { return AllOf(Field(&BitrateAllocationLimits::min_allocatable_rate, DataRate::BitsPerSec(min_allocatable_rate_bps)), Field(&BitrateAllocationLimits::max_padding_rate, DataRate::BitsPerSec(max_padding_rate_bps))); } class MockLimitObserver : public BitrateAllocator::LimitObserver { public: MOCK_METHOD(void, OnAllocationLimitsChanged, (BitrateAllocationLimits), (override)); }; class TestBitrateObserver : public BitrateAllocatorObserver { public: TestBitrateObserver() : last_bitrate_bps_(0), last_fraction_loss_(0), last_rtt_ms_(0), last_probing_interval_ms_(0), protection_ratio_(0.0) {} void SetBitrateProtectionRatio(double protection_ratio) { protection_ratio_ = protection_ratio; } uint32_t OnBitrateUpdated(BitrateAllocationUpdate update) override { last_bitrate_bps_ = update.target_bitrate.bps(); last_fraction_loss_ = rtc::dchecked_cast(update.packet_loss_ratio * 256); last_rtt_ms_ = update.round_trip_time.ms(); last_probing_interval_ms_ = update.bwe_period.ms(); return update.target_bitrate.bps() * protection_ratio_; } uint32_t last_bitrate_bps_; uint8_t last_fraction_loss_; int64_t last_rtt_ms_; int last_probing_interval_ms_; double protection_ratio_; }; constexpr int64_t kDefaultProbingIntervalMs = 3000; const double kDefaultBitratePriority = 1.0; TargetTransferRate CreateTargetRateMessage(uint32_t target_bitrate_bps, uint8_t fraction_loss, int64_t rtt_ms, int64_t bwe_period_ms) { TargetTransferRate msg; // The timestamp is just for log output, keeping it fixed just means fewer log // messages in the test. msg.at_time = Timestamp::Seconds(10000); msg.target_rate = DataRate::BitsPerSec(target_bitrate_bps); msg.stable_target_rate = msg.target_rate; msg.network_estimate.bandwidth = msg.target_rate; msg.network_estimate.loss_rate_ratio = fraction_loss / 255.0; msg.network_estimate.round_trip_time = TimeDelta::Millis(rtt_ms); msg.network_estimate.bwe_period = TimeDelta::Millis(bwe_period_ms); return msg; } } // namespace class BitrateAllocatorTest : public ::testing::Test { protected: BitrateAllocatorTest() : allocator_(new BitrateAllocator(&limit_observer_)) { allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(300000u, 0, 0, kDefaultProbingIntervalMs)); } ~BitrateAllocatorTest() {} void AddObserver(BitrateAllocatorObserver* observer, uint32_t min_bitrate_bps, uint32_t max_bitrate_bps, uint32_t pad_up_bitrate_bps, bool enforce_min_bitrate, double bitrate_priority) { allocator_->AddObserver( observer, {min_bitrate_bps, max_bitrate_bps, pad_up_bitrate_bps, /* priority_bitrate */ 0, enforce_min_bitrate, bitrate_priority}); } MediaStreamAllocationConfig DefaultConfig() const { MediaStreamAllocationConfig default_config; default_config.min_bitrate_bps = 0; default_config.max_bitrate_bps = 1500000; default_config.pad_up_bitrate_bps = 0; default_config.priority_bitrate_bps = 0; default_config.enforce_min_bitrate = true; default_config.bitrate_priority = kDefaultBitratePriority; return default_config; } NiceMock limit_observer_; std::unique_ptr allocator_; }; TEST_F(BitrateAllocatorTest, RespectsPriorityBitrate) { TestBitrateObserver stream_a; auto config_a = DefaultConfig(); config_a.min_bitrate_bps = 100000; config_a.priority_bitrate_bps = 0; allocator_->AddObserver(&stream_a, config_a); TestBitrateObserver stream_b; auto config_b = DefaultConfig(); config_b.min_bitrate_bps = 100000; config_b.max_bitrate_bps = 300000; config_b.priority_bitrate_bps = 300000; allocator_->AddObserver(&stream_b, config_b); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(100000, 0, 0, 0)); EXPECT_EQ(stream_a.last_bitrate_bps_, 100000u); EXPECT_EQ(stream_b.last_bitrate_bps_, 100000u); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(200000, 0, 0, 0)); EXPECT_EQ(stream_a.last_bitrate_bps_, 100000u); EXPECT_EQ(stream_b.last_bitrate_bps_, 100000u); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(300000, 0, 0, 0)); EXPECT_EQ(stream_a.last_bitrate_bps_, 100000u); EXPECT_EQ(stream_b.last_bitrate_bps_, 200000u); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(400000, 0, 0, 0)); EXPECT_EQ(stream_a.last_bitrate_bps_, 100000u); EXPECT_EQ(stream_b.last_bitrate_bps_, 300000u); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(800000, 0, 0, 0)); EXPECT_EQ(stream_a.last_bitrate_bps_, 500000u); EXPECT_EQ(stream_b.last_bitrate_bps_, 300000u); } TEST_F(BitrateAllocatorTest, UpdatingBitrateObserver) { TestBitrateObserver bitrate_observer; const uint32_t kMinSendBitrateBps = 100000; const uint32_t kPadUpToBitrateBps = 50000; const uint32_t kMaxBitrateBps = 1500000; EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(AllocationLimitsEq( kMinSendBitrateBps, kPadUpToBitrateBps, kMaxBitrateBps))); AddObserver(&bitrate_observer, kMinSendBitrateBps, kMaxBitrateBps, kPadUpToBitrateBps, true, kDefaultBitratePriority); EXPECT_EQ(300000, allocator_->GetStartBitrate(&bitrate_observer)); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(200000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(200000, allocator_->GetStartBitrate(&bitrate_observer)); // TODO(pbos): Expect capping to 1.5M instead of 3M when not boosting the max // bitrate for FEC/retransmissions (see todo in BitrateAllocator). allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(4000000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(3000000, allocator_->GetStartBitrate(&bitrate_observer)); // Expect `max_padding_bitrate_bps` to change to 0 if the observer is updated. EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged( AllocationLimitsEq(kMinSendBitrateBps, 0))); AddObserver(&bitrate_observer, kMinSendBitrateBps, 4000000, 0, true, kDefaultBitratePriority); EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged( AllocationLimitsEq(kMinSendBitrateBps, 0))); EXPECT_EQ(4000000, allocator_->GetStartBitrate(&bitrate_observer)); AddObserver(&bitrate_observer, kMinSendBitrateBps, kMaxBitrateBps, 0, true, kDefaultBitratePriority); EXPECT_EQ(3000000, allocator_->GetStartBitrate(&bitrate_observer)); EXPECT_EQ(3000000u, bitrate_observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(kMaxBitrateBps, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(1500000u, bitrate_observer.last_bitrate_bps_); } TEST_F(BitrateAllocatorTest, TwoBitrateObserversOneRtcpObserver) { TestBitrateObserver bitrate_observer_1; TestBitrateObserver bitrate_observer_2; const uint32_t kObs1StartBitrateBps = 100000; const uint32_t kObs2StartBitrateBps = 200000; const uint32_t kObs1MaxBitrateBps = 300000; const uint32_t kObs2MaxBitrateBps = 300000; EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(AllocationLimitsEq( kObs1StartBitrateBps, 0, kObs1MaxBitrateBps))); AddObserver(&bitrate_observer_1, kObs1StartBitrateBps, kObs1MaxBitrateBps, 0, true, kDefaultBitratePriority); EXPECT_EQ(static_cast(kObs1MaxBitrateBps), allocator_->GetStartBitrate(&bitrate_observer_1)); EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(AllocationLimitsEq( kObs1StartBitrateBps + kObs2StartBitrateBps, 0, kObs1MaxBitrateBps + kObs2MaxBitrateBps))); AddObserver(&bitrate_observer_2, kObs2StartBitrateBps, kObs2MaxBitrateBps, 0, true, kDefaultBitratePriority); EXPECT_EQ(static_cast(kObs2StartBitrateBps), allocator_->GetStartBitrate(&bitrate_observer_2)); // Test too low start bitrate, hence lower than sum of min. Min bitrates // will // be allocated to all observers. allocator_->OnNetworkEstimateChanged(CreateTargetRateMessage( kObs2StartBitrateBps, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(0, bitrate_observer_1.last_fraction_loss_); EXPECT_EQ(50, bitrate_observer_1.last_rtt_ms_); EXPECT_EQ(200000u, bitrate_observer_2.last_bitrate_bps_); EXPECT_EQ(0, bitrate_observer_2.last_fraction_loss_); EXPECT_EQ(50, bitrate_observer_2.last_rtt_ms_); // Test a bitrate which should be distributed equally. allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(500000, 0, 50, kDefaultProbingIntervalMs)); const uint32_t kBitrateToShare = 500000 - kObs2StartBitrateBps - kObs1StartBitrateBps; EXPECT_EQ(100000u + kBitrateToShare / 2, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(200000u + kBitrateToShare / 2, bitrate_observer_2.last_bitrate_bps_); // Limited by 2x max bitrates since we leave room for FEC and // retransmissions. allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(1500000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(600000u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(600000u, bitrate_observer_2.last_bitrate_bps_); // Verify that if the bandwidth estimate is set to zero, the allocated // rate is // zero. allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(0, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_bps_); } TEST_F(BitrateAllocatorTest, RemoveObserverTriggersLimitObserver) { TestBitrateObserver bitrate_observer; const uint32_t kMinSendBitrateBps = 100000; const uint32_t kPadUpToBitrateBps = 50000; const uint32_t kMaxBitrateBps = 1500000; EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(AllocationLimitsEq( kMinSendBitrateBps, kPadUpToBitrateBps, kMaxBitrateBps))); AddObserver(&bitrate_observer, kMinSendBitrateBps, kMaxBitrateBps, kPadUpToBitrateBps, true, kDefaultBitratePriority); EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(AllocationLimitsEq(0, 0))); allocator_->RemoveObserver(&bitrate_observer); } class BitrateAllocatorTestNoEnforceMin : public ::testing::Test { protected: BitrateAllocatorTestNoEnforceMin() : allocator_(new BitrateAllocator(&limit_observer_)) { allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(300000u, 0, 0, kDefaultProbingIntervalMs)); } ~BitrateAllocatorTestNoEnforceMin() {} void AddObserver(BitrateAllocatorObserver* observer, uint32_t min_bitrate_bps, uint32_t max_bitrate_bps, uint32_t pad_up_bitrate_bps, bool enforce_min_bitrate, absl::string_view track_id, double bitrate_priority) { allocator_->AddObserver( observer, {min_bitrate_bps, max_bitrate_bps, pad_up_bitrate_bps, 0, enforce_min_bitrate, bitrate_priority}); } NiceMock limit_observer_; std::unique_ptr allocator_; }; // The following three tests verify enforcing a minimum bitrate works as // intended. TEST_F(BitrateAllocatorTestNoEnforceMin, OneBitrateObserver) { TestBitrateObserver bitrate_observer_1; // Expect OnAllocationLimitsChanged with `min_send_bitrate_bps` = 0 since // AddObserver is called with `enforce_min_bitrate` = false. EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(AllocationLimitsEq(0, 0))); EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(AllocationLimitsEq(0, 120000))); AddObserver(&bitrate_observer_1, 100000, 400000, 0, false, "", kDefaultBitratePriority); EXPECT_EQ(300000, allocator_->GetStartBitrate(&bitrate_observer_1)); // High BWE. allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(150000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(150000u, bitrate_observer_1.last_bitrate_bps_); // Low BWE. allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(10000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_bps_); EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(AllocationLimitsEq(0, 0))); allocator_->RemoveObserver(&bitrate_observer_1); } TEST_F(BitrateAllocatorTestNoEnforceMin, ThreeBitrateObservers) { TestBitrateObserver bitrate_observer_1; TestBitrateObserver bitrate_observer_2; TestBitrateObserver bitrate_observer_3; // Set up the observers with min bitrates at 100000, 200000, and 300000. AddObserver(&bitrate_observer_1, 100000, 400000, 0, false, "", kDefaultBitratePriority); EXPECT_EQ(300000, allocator_->GetStartBitrate(&bitrate_observer_1)); AddObserver(&bitrate_observer_2, 200000, 400000, 0, false, "", kDefaultBitratePriority); EXPECT_EQ(200000, allocator_->GetStartBitrate(&bitrate_observer_2)); EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_); AddObserver(&bitrate_observer_3, 300000, 400000, 0, false, "", kDefaultBitratePriority); EXPECT_EQ(0, allocator_->GetStartBitrate(&bitrate_observer_3)); EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(200000u, bitrate_observer_2.last_bitrate_bps_); // High BWE. Make sure the controllers get a fair share of the surplus (i.e., // what is left after each controller gets its min rate). allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(690000, 0, 0, kDefaultProbingIntervalMs)); // Verify that each observer gets its min rate (sum of min rates is 600000), // and that the remaining 90000 is divided equally among the three. uint32_t bitrate_to_share = 690000u - 100000u - 200000u - 300000u; EXPECT_EQ(100000u + bitrate_to_share / 3, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(200000u + bitrate_to_share / 3, bitrate_observer_2.last_bitrate_bps_); EXPECT_EQ(300000u + bitrate_to_share / 3, bitrate_observer_3.last_bitrate_bps_); // BWE below the sum of observer's min bitrate. allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(300000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_); // Min bitrate. EXPECT_EQ(200000u, bitrate_observer_2.last_bitrate_bps_); // Min bitrate. EXPECT_EQ(0u, bitrate_observer_3.last_bitrate_bps_); // Nothing. // Increased BWE, but still below the sum of configured min bitrates for all // observers and too little for observer 3. 1 and 2 will share the rest. allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(500000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(200000u, bitrate_observer_1.last_bitrate_bps_); // Min + split. EXPECT_EQ(300000u, bitrate_observer_2.last_bitrate_bps_); // Min + split. EXPECT_EQ(0u, bitrate_observer_3.last_bitrate_bps_); // Nothing. // Below min for all. allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(10000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_bps_); EXPECT_EQ(0u, bitrate_observer_3.last_bitrate_bps_); // Verify that zero estimated bandwidth, means that that all gets zero, // regardless of set min bitrate. allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(0, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_bps_); EXPECT_EQ(0u, bitrate_observer_3.last_bitrate_bps_); allocator_->RemoveObserver(&bitrate_observer_1); allocator_->RemoveObserver(&bitrate_observer_2); allocator_->RemoveObserver(&bitrate_observer_3); } TEST_F(BitrateAllocatorTestNoEnforceMin, OneBitrateObserverWithPacketLoss) { const uint32_t kMinBitrateBps = 100000; const uint32_t kMaxBitrateBps = 400000; // Hysteresis adds another 10% or 20kbps to min bitrate. const uint32_t kMinStartBitrateBps = kMinBitrateBps + std::max(20000u, kMinBitrateBps / 10); // Expect OnAllocationLimitsChanged with `min_send_bitrate_bps` = 0 since // AddObserver is called with `enforce_min_bitrate` = false. TestBitrateObserver bitrate_observer; EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged( AllocationLimitsEq(0, 0, kMaxBitrateBps))); AddObserver(&bitrate_observer, kMinBitrateBps, kMaxBitrateBps, 0, false, "", kDefaultBitratePriority); EXPECT_EQ(300000, allocator_->GetStartBitrate(&bitrate_observer)); // High BWE. allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(150000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(150000u, bitrate_observer.last_bitrate_bps_); // Add loss and use a part of the bitrate for protection. const double kProtectionRatio = 0.4; const uint8_t fraction_loss = kProtectionRatio * 256; bitrate_observer.SetBitrateProtectionRatio(kProtectionRatio); allocator_->OnNetworkEstimateChanged(CreateTargetRateMessage( 200000, 0, fraction_loss, kDefaultProbingIntervalMs)); EXPECT_EQ(200000u, bitrate_observer.last_bitrate_bps_); // Above the min threshold, but not enough given the protection used. // Limits changed, as we will video is now off and we need to pad up to the // start bitrate. // Verify the hysteresis is added for the protection. const uint32_t kMinStartBitrateWithProtectionBps = static_cast(kMinStartBitrateBps * (1 + kProtectionRatio)); EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(AllocationLimitsEq( 0, kMinStartBitrateWithProtectionBps, kMaxBitrateBps))); allocator_->OnNetworkEstimateChanged(CreateTargetRateMessage( kMinStartBitrateBps + 1000, 0, fraction_loss, kDefaultProbingIntervalMs)); EXPECT_EQ(0u, bitrate_observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(kMinStartBitrateWithProtectionBps - 1000, 0, fraction_loss, kDefaultProbingIntervalMs)); EXPECT_EQ(0u, bitrate_observer.last_bitrate_bps_); // Just enough to enable video again. EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged( AllocationLimitsEq(0, 0, kMaxBitrateBps))); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(kMinStartBitrateWithProtectionBps, 0, fraction_loss, kDefaultProbingIntervalMs)); EXPECT_EQ(kMinStartBitrateWithProtectionBps, bitrate_observer.last_bitrate_bps_); // Remove all protection and make sure video is not paused as earlier. bitrate_observer.SetBitrateProtectionRatio(0.0); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(kMinStartBitrateWithProtectionBps - 1000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(kMinStartBitrateWithProtectionBps - 1000, bitrate_observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged(CreateTargetRateMessage( kMinStartBitrateBps, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(kMinStartBitrateBps, bitrate_observer.last_bitrate_bps_); EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(AllocationLimitsEq(0, 0, 0))); allocator_->RemoveObserver(&bitrate_observer); } TEST_F(BitrateAllocatorTest, TotalAllocationLimitsAreUnaffectedByProtectionRatio) { TestBitrateObserver bitrate_observer; const uint32_t kMinBitrateBps = 100000; const uint32_t kMaxBitrateBps = 400000; // Register `bitrate_observer` and expect total allocation limits to change. EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(AllocationLimitsEq( kMinBitrateBps, 0, kMaxBitrateBps))) .Times(1); MediaStreamAllocationConfig allocation_config = DefaultConfig(); allocation_config.min_bitrate_bps = kMinBitrateBps; allocation_config.max_bitrate_bps = kMaxBitrateBps; allocator_->AddObserver(&bitrate_observer, allocation_config); // Observer uses 20% of it's allocated bitrate for protection. bitrate_observer.SetBitrateProtectionRatio(/*protection_ratio=*/0.2); // Total allocation limits are unaffected by the protection rate change. EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(_)).Times(0); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(200000u, 0, 100, kDefaultProbingIntervalMs)); // Observer uses 0% of it's allocated bitrate for protection. bitrate_observer.SetBitrateProtectionRatio(/*protection_ratio=*/0.0); // Total allocation limits are unaffected by the protection rate change. EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(_)).Times(0); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(200000u, 0, 100, kDefaultProbingIntervalMs)); // Observer again uses 20% of it's allocated bitrate for protection. bitrate_observer.SetBitrateProtectionRatio(/*protection_ratio=*/0.2); // Total allocation limits are unaffected by the protection rate change. EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(_)).Times(0); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(200000u, 0, 100, kDefaultProbingIntervalMs)); } TEST_F(BitrateAllocatorTestNoEnforceMin, TwoBitrateObserverWithPacketLoss) { TestBitrateObserver bitrate_observer_1; TestBitrateObserver bitrate_observer_2; AddObserver(&bitrate_observer_1, 100000, 400000, 0, false, "", kDefaultBitratePriority); EXPECT_EQ(300000, allocator_->GetStartBitrate(&bitrate_observer_1)); AddObserver(&bitrate_observer_2, 200000, 400000, 0, false, "", kDefaultBitratePriority); EXPECT_EQ(200000, allocator_->GetStartBitrate(&bitrate_observer_2)); EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_); // Enough bitrate for both. bitrate_observer_2.SetBitrateProtectionRatio(0.5); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(300000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(200000u, bitrate_observer_2.last_bitrate_bps_); // Above min for observer 2, but too little given the protection used. allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(330000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(330000u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(100000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(99999, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(119000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(120000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(120000u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_bps_); // Verify the protection is accounted for before resuming observer 2. allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(429000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(400000u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(430000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(330000u, bitrate_observer_2.last_bitrate_bps_); allocator_->RemoveObserver(&bitrate_observer_1); allocator_->RemoveObserver(&bitrate_observer_2); } TEST_F(BitrateAllocatorTest, ThreeBitrateObserversLowBweEnforceMin) { TestBitrateObserver bitrate_observer_1; TestBitrateObserver bitrate_observer_2; TestBitrateObserver bitrate_observer_3; AddObserver(&bitrate_observer_1, 100000, 400000, 0, true, kDefaultBitratePriority); EXPECT_EQ(300000, allocator_->GetStartBitrate(&bitrate_observer_1)); AddObserver(&bitrate_observer_2, 200000, 400000, 0, true, kDefaultBitratePriority); EXPECT_EQ(200000, allocator_->GetStartBitrate(&bitrate_observer_2)); EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_); AddObserver(&bitrate_observer_3, 300000, 400000, 0, true, kDefaultBitratePriority); EXPECT_EQ(300000, allocator_->GetStartBitrate(&bitrate_observer_3)); EXPECT_EQ(100000, static_cast(bitrate_observer_1.last_bitrate_bps_)); EXPECT_EQ(200000, static_cast(bitrate_observer_2.last_bitrate_bps_)); // Low BWE. Verify that all observers still get their respective min // bitrate. allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(1000, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_); // Min cap. EXPECT_EQ(200000u, bitrate_observer_2.last_bitrate_bps_); // Min cap. EXPECT_EQ(300000u, bitrate_observer_3.last_bitrate_bps_); // Min cap. allocator_->RemoveObserver(&bitrate_observer_1); allocator_->RemoveObserver(&bitrate_observer_2); allocator_->RemoveObserver(&bitrate_observer_3); } TEST_F(BitrateAllocatorTest, AddObserverWhileNetworkDown) { TestBitrateObserver bitrate_observer_1; EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(AllocationLimitsEq(50000, 0))); AddObserver(&bitrate_observer_1, 50000, 400000, 0, true, kDefaultBitratePriority); EXPECT_EQ(300000, allocator_->GetStartBitrate(&bitrate_observer_1)); // Set network down, ie, no available bitrate. allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(0, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_bps_); TestBitrateObserver bitrate_observer_2; // Adding an observer while the network is down should not affect the limits. EXPECT_CALL(limit_observer_, OnAllocationLimitsChanged(AllocationLimitsEq(50000 + 50000, 0))); AddObserver(&bitrate_observer_2, 50000, 400000, 0, true, kDefaultBitratePriority); // Expect the start_bitrate to be set as if the network was still up but that // the new observer have been notified that the network is down. EXPECT_EQ(300000 / 2, allocator_->GetStartBitrate(&bitrate_observer_2)); EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_bps_); // Set network back up. allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(1500000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(750000u, bitrate_observer_1.last_bitrate_bps_); EXPECT_EQ(750000u, bitrate_observer_2.last_bitrate_bps_); } TEST_F(BitrateAllocatorTest, MixedEnforecedConfigs) { TestBitrateObserver enforced_observer; AddObserver(&enforced_observer, 6000, 30000, 0, true, kDefaultBitratePriority); EXPECT_EQ(60000, allocator_->GetStartBitrate(&enforced_observer)); TestBitrateObserver not_enforced_observer; AddObserver(¬_enforced_observer, 30000, 2500000, 0, false, kDefaultBitratePriority); EXPECT_EQ(270000, allocator_->GetStartBitrate(¬_enforced_observer)); EXPECT_EQ(30000u, enforced_observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(36000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(6000u, enforced_observer.last_bitrate_bps_); EXPECT_EQ(30000u, not_enforced_observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(35000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(30000u, enforced_observer.last_bitrate_bps_); EXPECT_EQ(0u, not_enforced_observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(5000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(6000u, enforced_observer.last_bitrate_bps_); EXPECT_EQ(0u, not_enforced_observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(36000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(30000u, enforced_observer.last_bitrate_bps_); EXPECT_EQ(0u, not_enforced_observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(55000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(30000u, enforced_observer.last_bitrate_bps_); EXPECT_EQ(0u, not_enforced_observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(56000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(6000u, enforced_observer.last_bitrate_bps_); EXPECT_EQ(50000u, not_enforced_observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(56000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(16000u, enforced_observer.last_bitrate_bps_); EXPECT_EQ(40000u, not_enforced_observer.last_bitrate_bps_); allocator_->RemoveObserver(&enforced_observer); allocator_->RemoveObserver(¬_enforced_observer); } TEST_F(BitrateAllocatorTest, AvoidToggleAbsolute) { TestBitrateObserver observer; AddObserver(&observer, 30000, 300000, 0, false, kDefaultBitratePriority); EXPECT_EQ(300000, allocator_->GetStartBitrate(&observer)); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(30000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(30000u, observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(20000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(0u, observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(30000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(0u, observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(49000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(0u, observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(50000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(50000u, observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(30000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(30000u, observer.last_bitrate_bps_); allocator_->RemoveObserver(&observer); } TEST_F(BitrateAllocatorTest, AvoidTogglePercent) { TestBitrateObserver observer; AddObserver(&observer, 300000, 600000, 0, false, kDefaultBitratePriority); EXPECT_EQ(300000, allocator_->GetStartBitrate(&observer)); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(300000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(300000u, observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(200000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(0u, observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(300000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(0u, observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(329000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(0u, observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(330000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(330000u, observer.last_bitrate_bps_); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(300000, 0, 50, kDefaultProbingIntervalMs)); EXPECT_EQ(300000u, observer.last_bitrate_bps_); allocator_->RemoveObserver(&observer); } TEST_F(BitrateAllocatorTest, PassProbingInterval) { TestBitrateObserver observer; AddObserver(&observer, 300000, 600000, 0, false, kDefaultBitratePriority); EXPECT_EQ(300000, allocator_->GetStartBitrate(&observer)); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(300000, 0, 50, 5000)); EXPECT_EQ(5000, observer.last_probing_interval_ms_); allocator_->RemoveObserver(&observer); } TEST_F(BitrateAllocatorTest, PriorityRateOneObserverBasic) { TestBitrateObserver observer; const uint32_t kMinSendBitrateBps = 10; const uint32_t kMaxSendBitrateBps = 60; const uint32_t kNetworkBandwidthBps = 30; AddObserver(&observer, kMinSendBitrateBps, kMaxSendBitrateBps, 0, true, 2.0); allocator_->OnNetworkEstimateChanged(CreateTargetRateMessage( kNetworkBandwidthBps, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(kNetworkBandwidthBps, observer.last_bitrate_bps_); allocator_->RemoveObserver(&observer); } // Tests that two observers with the same bitrate priority are allocated // their bitrate evenly. TEST_F(BitrateAllocatorTest, PriorityRateTwoObserversBasic) { TestBitrateObserver observer_low_1; TestBitrateObserver observer_low_2; const uint32_t kMinSendBitrateBps = 10; const uint32_t kMaxSendBitrateBps = 60; const uint32_t kNetworkBandwidthBps = 60; AddObserver(&observer_low_1, kMinSendBitrateBps, kMaxSendBitrateBps, 0, false, 2.0); AddObserver(&observer_low_2, kMinSendBitrateBps, kMaxSendBitrateBps, 0, false, 2.0); allocator_->OnNetworkEstimateChanged(CreateTargetRateMessage( kNetworkBandwidthBps, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(kNetworkBandwidthBps / 2, observer_low_1.last_bitrate_bps_); EXPECT_EQ(kNetworkBandwidthBps / 2, observer_low_2.last_bitrate_bps_); allocator_->RemoveObserver(&observer_low_1); allocator_->RemoveObserver(&observer_low_2); } // Tests that there is no difference in functionality when the min bitrate is // enforced. TEST_F(BitrateAllocatorTest, PriorityRateTwoObserversBasicMinEnforced) { TestBitrateObserver observer_low_1; TestBitrateObserver observer_low_2; const uint32_t kMinSendBitrateBps = 0; const uint32_t kMaxSendBitrateBps = 60; const uint32_t kNetworkBandwidthBps = 60; AddObserver(&observer_low_1, kMinSendBitrateBps, kMaxSendBitrateBps, 0, true, 2.0); AddObserver(&observer_low_2, kMinSendBitrateBps, kMaxSendBitrateBps, 0, true, 2.0); allocator_->OnNetworkEstimateChanged(CreateTargetRateMessage( kNetworkBandwidthBps, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(kNetworkBandwidthBps / 2, observer_low_1.last_bitrate_bps_); EXPECT_EQ(kNetworkBandwidthBps / 2, observer_low_2.last_bitrate_bps_); allocator_->RemoveObserver(&observer_low_1); allocator_->RemoveObserver(&observer_low_2); } // Tests that if the available bandwidth is the sum of the max bitrate // of all observers, they will be allocated their max. TEST_F(BitrateAllocatorTest, PriorityRateTwoObserversBothAllocatedMax) { TestBitrateObserver observer_low; TestBitrateObserver observer_mid; const uint32_t kMinSendBitrateBps = 0; const uint32_t kMaxSendBitrateBps = 60; const uint32_t kNetworkBandwidthBps = kMaxSendBitrateBps * 2; AddObserver(&observer_low, kMinSendBitrateBps, kMaxSendBitrateBps, 0, true, 2.0); AddObserver(&observer_mid, kMinSendBitrateBps, kMaxSendBitrateBps, 0, true, 4.0); allocator_->OnNetworkEstimateChanged(CreateTargetRateMessage( kNetworkBandwidthBps, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(kMaxSendBitrateBps, observer_low.last_bitrate_bps_); EXPECT_EQ(kMaxSendBitrateBps, observer_mid.last_bitrate_bps_); allocator_->RemoveObserver(&observer_low); allocator_->RemoveObserver(&observer_mid); } // Tests that after a higher bitrate priority observer has been allocated its // max bitrate the lower priority observer will then be allocated the remaining // bitrate. TEST_F(BitrateAllocatorTest, PriorityRateTwoObserversOneAllocatedToMax) { TestBitrateObserver observer_low; TestBitrateObserver observer_mid; AddObserver(&observer_low, 10, 50, 0, false, 2.0); AddObserver(&observer_mid, 10, 50, 0, false, 4.0); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(90, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(40u, observer_low.last_bitrate_bps_); EXPECT_EQ(50u, observer_mid.last_bitrate_bps_); allocator_->RemoveObserver(&observer_low); allocator_->RemoveObserver(&observer_mid); } // Tests that three observers with three different bitrate priorities will all // be allocated bitrate according to their relative bitrate priority. TEST_F(BitrateAllocatorTest, PriorityRateThreeObserversAllocatedRelativeAmounts) { TestBitrateObserver observer_low; TestBitrateObserver observer_mid; TestBitrateObserver observer_high; const uint32_t kMaxBitrate = 100; // Not enough bandwidth to fill any observer's max bitrate. const uint32_t kNetworkBandwidthBps = 70; const double kLowBitratePriority = 2.0; const double kMidBitratePriority = 4.0; const double kHighBitratePriority = 8.0; const double kTotalBitratePriority = kLowBitratePriority + kMidBitratePriority + kHighBitratePriority; AddObserver(&observer_low, 0, kMaxBitrate, 0, false, kLowBitratePriority); AddObserver(&observer_mid, 0, kMaxBitrate, 0, false, kMidBitratePriority); AddObserver(&observer_high, 0, kMaxBitrate, 0, false, kHighBitratePriority); allocator_->OnNetworkEstimateChanged(CreateTargetRateMessage( kNetworkBandwidthBps, 0, 0, kDefaultProbingIntervalMs)); const double kLowFractionAllocated = kLowBitratePriority / kTotalBitratePriority; const double kMidFractionAllocated = kMidBitratePriority / kTotalBitratePriority; const double kHighFractionAllocated = kHighBitratePriority / kTotalBitratePriority; EXPECT_EQ(kLowFractionAllocated * kNetworkBandwidthBps, observer_low.last_bitrate_bps_); EXPECT_EQ(kMidFractionAllocated * kNetworkBandwidthBps, observer_mid.last_bitrate_bps_); EXPECT_EQ(kHighFractionAllocated * kNetworkBandwidthBps, observer_high.last_bitrate_bps_); allocator_->RemoveObserver(&observer_low); allocator_->RemoveObserver(&observer_mid); allocator_->RemoveObserver(&observer_high); } // Tests that after the high priority observer has been allocated its maximum // bitrate, the other two observers are still allocated bitrate according to // their relative bitrate priority. TEST_F(BitrateAllocatorTest, PriorityRateThreeObserversHighAllocatedToMax) { TestBitrateObserver observer_low; const double kLowBitratePriority = 2.0; TestBitrateObserver observer_mid; const double kMidBitratePriority = 4.0; TestBitrateObserver observer_high; const double kHighBitratePriority = 8.0; const uint32_t kAvailableBitrate = 90; const uint32_t kMaxBitrate = 40; const uint32_t kMinBitrate = 10; // Remaining bitrate after allocating to all mins and knowing that the high // priority observer will have its max bitrate allocated. const uint32_t kRemainingBitrate = kAvailableBitrate - kMaxBitrate - (2 * kMinBitrate); AddObserver(&observer_low, kMinBitrate, kMaxBitrate, 0, false, kLowBitratePriority); AddObserver(&observer_mid, kMinBitrate, kMaxBitrate, 0, false, kMidBitratePriority); AddObserver(&observer_high, kMinBitrate, kMaxBitrate, 0, false, kHighBitratePriority); allocator_->OnNetworkEstimateChanged(CreateTargetRateMessage( kAvailableBitrate, 0, 0, kDefaultProbingIntervalMs)); const double kLowFractionAllocated = kLowBitratePriority / (kLowBitratePriority + kMidBitratePriority); const double kMidFractionAllocated = kMidBitratePriority / (kLowBitratePriority + kMidBitratePriority); EXPECT_EQ(kMinBitrate + (kRemainingBitrate * kLowFractionAllocated), observer_low.last_bitrate_bps_); EXPECT_EQ(kMinBitrate + (kRemainingBitrate * kMidFractionAllocated), observer_mid.last_bitrate_bps_); EXPECT_EQ(40u, observer_high.last_bitrate_bps_); allocator_->RemoveObserver(&observer_low); allocator_->RemoveObserver(&observer_mid); allocator_->RemoveObserver(&observer_high); } // Tests that after the low priority observer has been allocated its maximum // bitrate, the other two observers are still allocated bitrate according to // their relative bitrate priority. TEST_F(BitrateAllocatorTest, PriorityRateThreeObserversLowAllocatedToMax) { TestBitrateObserver observer_low; const double kLowBitratePriority = 2.0; const uint32_t kLowMaxBitrate = 10; TestBitrateObserver observer_mid; const double kMidBitratePriority = 4.0; TestBitrateObserver observer_high; const double kHighBitratePriority = 8.0; const uint32_t kMinBitrate = 0; const uint32_t kMaxBitrate = 60; const uint32_t kAvailableBitrate = 100; // Remaining bitrate knowing that the low priority observer is allocated its // max bitrate. We know this because it is allocated 2.0/14.0 (1/7) of the // available bitrate, so 70 bps would be sufficient network bandwidth. const uint32_t kRemainingBitrate = kAvailableBitrate - kLowMaxBitrate; AddObserver(&observer_low, kMinBitrate, kLowMaxBitrate, 0, false, kLowBitratePriority); AddObserver(&observer_mid, kMinBitrate, kMaxBitrate, 0, false, kMidBitratePriority); AddObserver(&observer_high, kMinBitrate, kMaxBitrate, 0, false, kHighBitratePriority); allocator_->OnNetworkEstimateChanged(CreateTargetRateMessage( kAvailableBitrate, 0, 0, kDefaultProbingIntervalMs)); const double kMidFractionAllocated = kMidBitratePriority / (kMidBitratePriority + kHighBitratePriority); const double kHighFractionAllocated = kHighBitratePriority / (kMidBitratePriority + kHighBitratePriority); EXPECT_EQ(kLowMaxBitrate, observer_low.last_bitrate_bps_); EXPECT_EQ(kMinBitrate + (kRemainingBitrate * kMidFractionAllocated), observer_mid.last_bitrate_bps_); EXPECT_EQ(kMinBitrate + (kRemainingBitrate * kHighFractionAllocated), observer_high.last_bitrate_bps_); allocator_->RemoveObserver(&observer_low); allocator_->RemoveObserver(&observer_mid); allocator_->RemoveObserver(&observer_high); } // Tests that after two observers are allocated bitrate to their max, the // the remaining observer is allocated what's left appropriately. This test // handles an edge case where the medium and high observer reach their // "relative" max allocation at the same time. The high has 40 to allocate // above its min, and the mid has 20 to allocate above its min, which scaled // by their bitrate priority is the same for each. TEST_F(BitrateAllocatorTest, PriorityRateThreeObserversTwoAllocatedToMax) { TestBitrateObserver observer_low; TestBitrateObserver observer_mid; TestBitrateObserver observer_high; AddObserver(&observer_low, 10, 40, 0, false, 2.0); // Scaled allocation above the min allocation is the same for these two, // meaning they will get allocated their max at the same time. // Scaled (target allocation) = (max - min) / bitrate priority AddObserver(&observer_mid, 10, 30, 0, false, 4.0); AddObserver(&observer_high, 10, 50, 0, false, 8.0); allocator_->OnNetworkEstimateChanged( CreateTargetRateMessage(110, 0, 0, kDefaultProbingIntervalMs)); EXPECT_EQ(30u, observer_low.last_bitrate_bps_); EXPECT_EQ(30u, observer_mid.last_bitrate_bps_); EXPECT_EQ(50u, observer_high.last_bitrate_bps_); allocator_->RemoveObserver(&observer_low); allocator_->RemoveObserver(&observer_mid); allocator_->RemoveObserver(&observer_high); } } // namespace webrtc