304 lines
14 KiB
C++
304 lines
14 KiB
C++
/*
|
|
* Copyright (c) 2018 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 "modules/congestion_controller/pcc/bitrate_controller.h"
|
|
|
|
#include <memory>
|
|
#include <utility>
|
|
|
|
#include "modules/congestion_controller/pcc/monitor_interval.h"
|
|
#include "test/gmock.h"
|
|
#include "test/gtest.h"
|
|
|
|
namespace webrtc {
|
|
namespace pcc {
|
|
namespace test {
|
|
namespace {
|
|
constexpr double kInitialConversionFactor = 1;
|
|
constexpr double kInitialDynamicBoundary = 0.05;
|
|
constexpr double kDynamicBoundaryIncrement = 0.1;
|
|
|
|
constexpr double kDelayGradientCoefficient = 900;
|
|
constexpr double kLossCoefficient = 11.35;
|
|
constexpr double kThroughputCoefficient = 500 * 1000;
|
|
constexpr double kThroughputPower = 0.99;
|
|
constexpr double kDelayGradientThreshold = 0.01;
|
|
constexpr double kDelayGradientNegativeBound = 10;
|
|
|
|
const DataRate kTargetSendingRate = DataRate::KilobitsPerSec(300);
|
|
const double kEpsilon = 0.05;
|
|
const Timestamp kStartTime = Timestamp::Micros(0);
|
|
const TimeDelta kPacketsDelta = TimeDelta::Millis(1);
|
|
const TimeDelta kIntervalDuration = TimeDelta::Millis(1000);
|
|
const TimeDelta kDefaultRtt = TimeDelta::Millis(1000);
|
|
const DataSize kDefaultDataSize = DataSize::Bytes(100);
|
|
|
|
std::vector<PacketResult> CreatePacketResults(
|
|
const std::vector<Timestamp>& packets_send_times,
|
|
const std::vector<Timestamp>& packets_received_times = {},
|
|
const std::vector<DataSize>& packets_sizes = {}) {
|
|
std::vector<PacketResult> packet_results;
|
|
PacketResult packet_result;
|
|
SentPacket sent_packet;
|
|
for (size_t i = 0; i < packets_send_times.size(); ++i) {
|
|
sent_packet.send_time = packets_send_times[i];
|
|
if (packets_sizes.empty()) {
|
|
sent_packet.size = kDefaultDataSize;
|
|
} else {
|
|
sent_packet.size = packets_sizes[i];
|
|
}
|
|
packet_result.sent_packet = sent_packet;
|
|
if (packets_received_times.empty()) {
|
|
packet_result.receive_time = packets_send_times[i] + kDefaultRtt;
|
|
} else {
|
|
packet_result.receive_time = packets_received_times[i];
|
|
}
|
|
packet_results.push_back(packet_result);
|
|
}
|
|
return packet_results;
|
|
}
|
|
|
|
class MockUtilityFunction : public PccUtilityFunctionInterface {
|
|
public:
|
|
MOCK_METHOD(double,
|
|
Compute,
|
|
(const PccMonitorInterval& monitor_interval),
|
|
(const, override));
|
|
};
|
|
|
|
} // namespace
|
|
|
|
TEST(PccBitrateControllerTest, IncreaseRateWhenNoChangesForTestBitrates) {
|
|
PccBitrateController bitrate_controller(
|
|
kInitialConversionFactor, kInitialDynamicBoundary,
|
|
kDynamicBoundaryIncrement, kDelayGradientCoefficient, kLossCoefficient,
|
|
kThroughputCoefficient, kThroughputPower, kDelayGradientThreshold,
|
|
kDelayGradientNegativeBound);
|
|
VivaceUtilityFunction utility_function(
|
|
kDelayGradientCoefficient, kLossCoefficient, kThroughputCoefficient,
|
|
kThroughputPower, kDelayGradientThreshold, kDelayGradientNegativeBound);
|
|
std::vector<PccMonitorInterval> monitor_block{
|
|
PccMonitorInterval(kTargetSendingRate * (1 + kEpsilon), kStartTime,
|
|
kIntervalDuration),
|
|
PccMonitorInterval(kTargetSendingRate * (1 - kEpsilon),
|
|
kStartTime + kIntervalDuration, kIntervalDuration)};
|
|
monitor_block[0].OnPacketsFeedback(
|
|
CreatePacketResults({kStartTime + kPacketsDelta,
|
|
kStartTime + kIntervalDuration + kPacketsDelta,
|
|
kStartTime + 3 * kIntervalDuration},
|
|
{}, {}));
|
|
monitor_block[1].OnPacketsFeedback(
|
|
CreatePacketResults({kStartTime + kPacketsDelta,
|
|
kStartTime + kIntervalDuration + kPacketsDelta,
|
|
kStartTime + 3 * kIntervalDuration},
|
|
{}, {}));
|
|
// For both of the monitor intervals there were no change in rtt gradient
|
|
// and in packet loss. Since the only difference is in the sending rate,
|
|
// the higher sending rate should be chosen by congestion controller.
|
|
EXPECT_GT(bitrate_controller
|
|
.ComputeRateUpdateForOnlineLearningMode(monitor_block,
|
|
kTargetSendingRate)
|
|
.bps(),
|
|
kTargetSendingRate.bps());
|
|
}
|
|
|
|
TEST(PccBitrateControllerTest, NoChangesWhenUtilityFunctionDoesntChange) {
|
|
std::unique_ptr<MockUtilityFunction> mock_utility_function =
|
|
std::make_unique<MockUtilityFunction>();
|
|
EXPECT_CALL(*mock_utility_function, Compute(::testing::_))
|
|
.Times(2)
|
|
.WillOnce(::testing::Return(100))
|
|
.WillOnce(::testing::Return(100));
|
|
|
|
PccBitrateController bitrate_controller(
|
|
kInitialConversionFactor, kInitialDynamicBoundary,
|
|
kDynamicBoundaryIncrement, std::move(mock_utility_function));
|
|
std::vector<PccMonitorInterval> monitor_block{
|
|
PccMonitorInterval(kTargetSendingRate * (1 + kEpsilon), kStartTime,
|
|
kIntervalDuration),
|
|
PccMonitorInterval(kTargetSendingRate * (1 - kEpsilon),
|
|
kStartTime + kIntervalDuration, kIntervalDuration)};
|
|
// To complete collecting feedback within monitor intervals.
|
|
monitor_block[0].OnPacketsFeedback(
|
|
CreatePacketResults({kStartTime + 3 * kIntervalDuration}, {}, {}));
|
|
monitor_block[1].OnPacketsFeedback(
|
|
CreatePacketResults({kStartTime + 3 * kIntervalDuration}, {}, {}));
|
|
// Because we don't have any packets inside of monitor intervals, utility
|
|
// function should be zero for both of them and the sending rate should not
|
|
// change.
|
|
EXPECT_EQ(bitrate_controller
|
|
.ComputeRateUpdateForOnlineLearningMode(monitor_block,
|
|
kTargetSendingRate)
|
|
.bps(),
|
|
kTargetSendingRate.bps());
|
|
}
|
|
|
|
TEST(PccBitrateControllerTest, NoBoundaryWhenSmallGradient) {
|
|
std::unique_ptr<MockUtilityFunction> mock_utility_function =
|
|
std::make_unique<MockUtilityFunction>();
|
|
constexpr double kFirstMonitorIntervalUtility = 0;
|
|
const double kSecondMonitorIntervalUtility =
|
|
2 * kTargetSendingRate.bps() * kEpsilon;
|
|
|
|
EXPECT_CALL(*mock_utility_function, Compute(::testing::_))
|
|
.Times(2)
|
|
.WillOnce(::testing::Return(kFirstMonitorIntervalUtility))
|
|
.WillOnce(::testing::Return(kSecondMonitorIntervalUtility));
|
|
|
|
PccBitrateController bitrate_controller(
|
|
kInitialConversionFactor, kInitialDynamicBoundary,
|
|
kDynamicBoundaryIncrement, std::move(mock_utility_function));
|
|
std::vector<PccMonitorInterval> monitor_block{
|
|
PccMonitorInterval(kTargetSendingRate * (1 + kEpsilon), kStartTime,
|
|
kIntervalDuration),
|
|
PccMonitorInterval(kTargetSendingRate * (1 - kEpsilon),
|
|
kStartTime + kIntervalDuration, kIntervalDuration)};
|
|
// To complete collecting feedback within monitor intervals.
|
|
monitor_block[0].OnPacketsFeedback(
|
|
CreatePacketResults({kStartTime + 3 * kIntervalDuration}, {}, {}));
|
|
monitor_block[1].OnPacketsFeedback(
|
|
CreatePacketResults({kStartTime + 3 * kIntervalDuration}, {}, {}));
|
|
|
|
double gradient =
|
|
(kFirstMonitorIntervalUtility - kSecondMonitorIntervalUtility) /
|
|
(kTargetSendingRate.bps() * 2 * kEpsilon);
|
|
// When the gradient is small we don't hit the dynamic boundary.
|
|
EXPECT_EQ(bitrate_controller
|
|
.ComputeRateUpdateForOnlineLearningMode(monitor_block,
|
|
kTargetSendingRate)
|
|
.bps(),
|
|
kTargetSendingRate.bps() + kInitialConversionFactor * gradient);
|
|
}
|
|
|
|
TEST(PccBitrateControllerTest, FaceBoundaryWhenLargeGradient) {
|
|
std::unique_ptr<MockUtilityFunction> mock_utility_function =
|
|
std::make_unique<MockUtilityFunction>();
|
|
constexpr double kFirstMonitorIntervalUtility = 0;
|
|
const double kSecondMonitorIntervalUtility =
|
|
10 * kInitialDynamicBoundary * kTargetSendingRate.bps() * 2 *
|
|
kTargetSendingRate.bps() * kEpsilon;
|
|
|
|
EXPECT_CALL(*mock_utility_function, Compute(::testing::_))
|
|
.Times(4)
|
|
.WillOnce(::testing::Return(kFirstMonitorIntervalUtility))
|
|
.WillOnce(::testing::Return(kSecondMonitorIntervalUtility))
|
|
.WillOnce(::testing::Return(kFirstMonitorIntervalUtility))
|
|
.WillOnce(::testing::Return(kSecondMonitorIntervalUtility));
|
|
|
|
PccBitrateController bitrate_controller(
|
|
kInitialConversionFactor, kInitialDynamicBoundary,
|
|
kDynamicBoundaryIncrement, std::move(mock_utility_function));
|
|
std::vector<PccMonitorInterval> monitor_block{
|
|
PccMonitorInterval(kTargetSendingRate * (1 + kEpsilon), kStartTime,
|
|
kIntervalDuration),
|
|
PccMonitorInterval(kTargetSendingRate * (1 - kEpsilon),
|
|
kStartTime + kIntervalDuration, kIntervalDuration)};
|
|
// To complete collecting feedback within monitor intervals.
|
|
monitor_block[0].OnPacketsFeedback(
|
|
CreatePacketResults({kStartTime + 3 * kIntervalDuration}, {}, {}));
|
|
monitor_block[1].OnPacketsFeedback(
|
|
CreatePacketResults({kStartTime + 3 * kIntervalDuration}, {}, {}));
|
|
// The utility function gradient is too big and we hit the dynamic boundary.
|
|
EXPECT_EQ(bitrate_controller.ComputeRateUpdateForOnlineLearningMode(
|
|
monitor_block, kTargetSendingRate),
|
|
kTargetSendingRate * (1 - kInitialDynamicBoundary));
|
|
// For the second time we hit the dynamic boundary in the same direction, the
|
|
// boundary should increase.
|
|
EXPECT_EQ(bitrate_controller
|
|
.ComputeRateUpdateForOnlineLearningMode(monitor_block,
|
|
kTargetSendingRate)
|
|
.bps(),
|
|
kTargetSendingRate.bps() *
|
|
(1 - kInitialDynamicBoundary - kDynamicBoundaryIncrement));
|
|
}
|
|
|
|
TEST(PccBitrateControllerTest, SlowStartMode) {
|
|
std::unique_ptr<MockUtilityFunction> mock_utility_function =
|
|
std::make_unique<MockUtilityFunction>();
|
|
constexpr double kFirstUtilityFunction = 1000;
|
|
EXPECT_CALL(*mock_utility_function, Compute(::testing::_))
|
|
.Times(4)
|
|
// For first 3 calls we expect to stay in the SLOW_START mode and double
|
|
// the sending rate since the utility function increases its value. For
|
|
// the last call utility function decreases its value, this means that
|
|
// we should not double the sending rate and exit SLOW_START mode.
|
|
.WillOnce(::testing::Return(kFirstUtilityFunction))
|
|
.WillOnce(::testing::Return(kFirstUtilityFunction + 1))
|
|
.WillOnce(::testing::Return(kFirstUtilityFunction + 2))
|
|
.WillOnce(::testing::Return(kFirstUtilityFunction + 1));
|
|
|
|
PccBitrateController bitrate_controller(
|
|
kInitialConversionFactor, kInitialDynamicBoundary,
|
|
kDynamicBoundaryIncrement, std::move(mock_utility_function));
|
|
std::vector<PccMonitorInterval> monitor_block{PccMonitorInterval(
|
|
2 * kTargetSendingRate, kStartTime, kIntervalDuration)};
|
|
// To complete collecting feedback within monitor intervals.
|
|
monitor_block[0].OnPacketsFeedback(
|
|
CreatePacketResults({kStartTime + 3 * kIntervalDuration}, {}, {}));
|
|
EXPECT_EQ(
|
|
bitrate_controller.ComputeRateUpdateForSlowStartMode(monitor_block[0]),
|
|
kTargetSendingRate * 2);
|
|
EXPECT_EQ(
|
|
bitrate_controller.ComputeRateUpdateForSlowStartMode(monitor_block[0]),
|
|
kTargetSendingRate * 2);
|
|
EXPECT_EQ(
|
|
bitrate_controller.ComputeRateUpdateForSlowStartMode(monitor_block[0]),
|
|
kTargetSendingRate * 2);
|
|
EXPECT_EQ(
|
|
bitrate_controller.ComputeRateUpdateForSlowStartMode(monitor_block[0]),
|
|
absl::nullopt);
|
|
}
|
|
|
|
TEST(PccBitrateControllerTest, StepSizeIncrease) {
|
|
std::unique_ptr<MockUtilityFunction> mock_utility_function =
|
|
std::make_unique<MockUtilityFunction>();
|
|
constexpr double kFirstMiUtilityFunction = 0;
|
|
const double kSecondMiUtilityFunction =
|
|
2 * kTargetSendingRate.bps() * kEpsilon;
|
|
|
|
EXPECT_CALL(*mock_utility_function, Compute(::testing::_))
|
|
.Times(4)
|
|
.WillOnce(::testing::Return(kFirstMiUtilityFunction))
|
|
.WillOnce(::testing::Return(kSecondMiUtilityFunction))
|
|
.WillOnce(::testing::Return(kFirstMiUtilityFunction))
|
|
.WillOnce(::testing::Return(kSecondMiUtilityFunction));
|
|
std::vector<PccMonitorInterval> monitor_block{
|
|
PccMonitorInterval(kTargetSendingRate * (1 + kEpsilon), kStartTime,
|
|
kIntervalDuration),
|
|
PccMonitorInterval(kTargetSendingRate * (1 - kEpsilon),
|
|
kStartTime + kIntervalDuration, kIntervalDuration)};
|
|
// To complete collecting feedback within monitor intervals.
|
|
monitor_block[0].OnPacketsFeedback(
|
|
CreatePacketResults({kStartTime + 3 * kIntervalDuration}, {}, {}));
|
|
monitor_block[1].OnPacketsFeedback(
|
|
CreatePacketResults({kStartTime + 3 * kIntervalDuration}, {}, {}));
|
|
|
|
double gradient = (kFirstMiUtilityFunction - kSecondMiUtilityFunction) /
|
|
(kTargetSendingRate.bps() * 2 * kEpsilon);
|
|
PccBitrateController bitrate_controller(
|
|
kInitialConversionFactor, kInitialDynamicBoundary,
|
|
kDynamicBoundaryIncrement, std::move(mock_utility_function));
|
|
// If we are moving in the same direction - the step size should increase.
|
|
EXPECT_EQ(bitrate_controller
|
|
.ComputeRateUpdateForOnlineLearningMode(monitor_block,
|
|
kTargetSendingRate)
|
|
.bps(),
|
|
kTargetSendingRate.bps() + kInitialConversionFactor * gradient);
|
|
EXPECT_EQ(bitrate_controller
|
|
.ComputeRateUpdateForOnlineLearningMode(monitor_block,
|
|
kTargetSendingRate)
|
|
.bps(),
|
|
kTargetSendingRate.bps() + 2 * kInitialConversionFactor * gradient);
|
|
}
|
|
|
|
} // namespace test
|
|
} // namespace pcc
|
|
} // namespace webrtc
|