blob: 3806ec28d22893a6428e01a3ad33317481a77d90 [file] [log] [blame]
/*
* Copyright (c) 2019 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "modules/pacing/task_queue_paced_sender.h"
#include <algorithm>
#include <list>
#include <memory>
#include <string>
#include <utility>
#include <vector>
#include "api/transport/network_types.h"
#include "modules/pacing/packet_router.h"
#include "modules/utility/include/mock/mock_process_thread.h"
#include "test/field_trial.h"
#include "test/gmock.h"
#include "test/gtest.h"
#include "test/time_controller/simulated_time_controller.h"
using ::testing::_;
using ::testing::AtLeast;
using ::testing::Return;
using ::testing::SaveArg;
namespace webrtc {
namespace {
constexpr uint32_t kAudioSsrc = 12345;
constexpr uint32_t kVideoSsrc = 234565;
constexpr uint32_t kVideoRtxSsrc = 34567;
constexpr uint32_t kFlexFecSsrc = 45678;
constexpr size_t kDefaultPacketSize = 1234;
class MockPacketRouter : public PacketRouter {
public:
MOCK_METHOD(void,
SendPacket,
(std::unique_ptr<RtpPacketToSend> packet,
const PacedPacketInfo& cluster_info),
(override));
MOCK_METHOD(std::vector<std::unique_ptr<RtpPacketToSend>>,
FetchFec,
(),
(override));
MOCK_METHOD(std::vector<std::unique_ptr<RtpPacketToSend>>,
GeneratePadding,
(DataSize target_size),
(override));
};
class StatsUpdateObserver {
public:
StatsUpdateObserver() = default;
virtual ~StatsUpdateObserver() = default;
virtual void OnStatsUpdated() = 0;
};
class TaskQueuePacedSenderForTest : public TaskQueuePacedSender {
public:
TaskQueuePacedSenderForTest(Clock* clock,
PacketRouter* packet_router,
RtcEventLog* event_log,
const WebRtcKeyValueConfig* field_trials,
TaskQueueFactory* task_queue_factory,
TimeDelta hold_back_window)
: TaskQueuePacedSender(clock,
packet_router,
event_log,
field_trials,
task_queue_factory,
hold_back_window) {}
void OnStatsUpdated(const Stats& stats) override {
++num_stats_updates_;
TaskQueuePacedSender::OnStatsUpdated(stats);
}
size_t num_stats_updates_ = 0;
};
std::vector<std::unique_ptr<RtpPacketToSend>> GeneratePadding(
DataSize target_size) {
// 224 bytes is the max padding size for plain padding packets generated by
// RTPSender::GeneratePadding().
const DataSize kMaxPaddingPacketSize = DataSize::Bytes(224);
DataSize padding_generated = DataSize::Zero();
std::vector<std::unique_ptr<RtpPacketToSend>> padding_packets;
while (padding_generated < target_size) {
DataSize packet_size =
std::min(target_size - padding_generated, kMaxPaddingPacketSize);
padding_generated += packet_size;
auto padding_packet =
std::make_unique<RtpPacketToSend>(/*extensions=*/nullptr);
padding_packet->set_packet_type(RtpPacketMediaType::kPadding);
padding_packet->SetPadding(packet_size.bytes());
padding_packets.push_back(std::move(padding_packet));
}
return padding_packets;
}
} // namespace
namespace test {
std::unique_ptr<RtpPacketToSend> BuildRtpPacket(RtpPacketMediaType type) {
auto packet = std::make_unique<RtpPacketToSend>(nullptr);
packet->set_packet_type(type);
switch (type) {
case RtpPacketMediaType::kAudio:
packet->SetSsrc(kAudioSsrc);
break;
case RtpPacketMediaType::kVideo:
packet->SetSsrc(kVideoSsrc);
break;
case RtpPacketMediaType::kRetransmission:
case RtpPacketMediaType::kPadding:
packet->SetSsrc(kVideoRtxSsrc);
break;
case RtpPacketMediaType::kForwardErrorCorrection:
packet->SetSsrc(kFlexFecSsrc);
break;
}
packet->SetPayloadSize(kDefaultPacketSize);
return packet;
}
std::vector<std::unique_ptr<RtpPacketToSend>> GeneratePackets(
RtpPacketMediaType type,
size_t num_packets) {
std::vector<std::unique_ptr<RtpPacketToSend>> packets;
for (size_t i = 0; i < num_packets; ++i) {
packets.push_back(BuildRtpPacket(type));
}
return packets;
}
TEST(TaskQueuePacedSenderTest, PacesPackets) {
GlobalSimulatedTimeController time_controller(Timestamp::Millis(1234));
MockPacketRouter packet_router;
TaskQueuePacedSenderForTest pacer(
time_controller.GetClock(), &packet_router,
/*event_log=*/nullptr,
/*field_trials=*/nullptr, time_controller.GetTaskQueueFactory(),
PacingController::kMinSleepTime);
// Insert a number of packets, covering one second.
static constexpr size_t kPacketsToSend = 42;
pacer.SetPacingRates(
DataRate::BitsPerSec(kDefaultPacketSize * 8 * kPacketsToSend),
DataRate::Zero());
pacer.EnsureStarted();
pacer.EnqueuePackets(
GeneratePackets(RtpPacketMediaType::kVideo, kPacketsToSend));
// Expect all of them to be sent.
size_t packets_sent = 0;
Timestamp end_time = Timestamp::PlusInfinity();
EXPECT_CALL(packet_router, SendPacket)
.WillRepeatedly([&](std::unique_ptr<RtpPacketToSend> packet,
const PacedPacketInfo& cluster_info) {
++packets_sent;
if (packets_sent == kPacketsToSend) {
end_time = time_controller.GetClock()->CurrentTime();
}
});
const Timestamp start_time = time_controller.GetClock()->CurrentTime();
// Packets should be sent over a period of close to 1s. Expect a little
// lower than this since initial probing is a bit quicker.
time_controller.AdvanceTime(TimeDelta::Seconds(1));
EXPECT_EQ(packets_sent, kPacketsToSend);
ASSERT_TRUE(end_time.IsFinite());
EXPECT_NEAR((end_time - start_time).ms<double>(), 1000.0, 50.0);
}
TEST(TaskQueuePacedSenderTest, ReschedulesProcessOnRateChange) {
GlobalSimulatedTimeController time_controller(Timestamp::Millis(1234));
MockPacketRouter packet_router;
TaskQueuePacedSenderForTest pacer(
time_controller.GetClock(), &packet_router,
/*event_log=*/nullptr,
/*field_trials=*/nullptr, time_controller.GetTaskQueueFactory(),
PacingController::kMinSleepTime);
// Insert a number of packets to be sent 200ms apart.
const size_t kPacketsPerSecond = 5;
const DataRate kPacingRate =
DataRate::BitsPerSec(kDefaultPacketSize * 8 * kPacketsPerSecond);
pacer.SetPacingRates(kPacingRate, DataRate::Zero());
pacer.EnsureStarted();
// Send some initial packets to be rid of any probes.
EXPECT_CALL(packet_router, SendPacket).Times(kPacketsPerSecond);
pacer.EnqueuePackets(
GeneratePackets(RtpPacketMediaType::kVideo, kPacketsPerSecond));
time_controller.AdvanceTime(TimeDelta::Seconds(1));
// Insert three packets, and record send time of each of them.
// After the second packet is sent, double the send rate so we can
// check the third packets is sent after half the wait time.
Timestamp first_packet_time = Timestamp::MinusInfinity();
Timestamp second_packet_time = Timestamp::MinusInfinity();
Timestamp third_packet_time = Timestamp::MinusInfinity();
EXPECT_CALL(packet_router, SendPacket)
.Times(3)
.WillRepeatedly([&](std::unique_ptr<RtpPacketToSend> packet,
const PacedPacketInfo& cluster_info) {
if (first_packet_time.IsInfinite()) {
first_packet_time = time_controller.GetClock()->CurrentTime();
} else if (second_packet_time.IsInfinite()) {
second_packet_time = time_controller.GetClock()->CurrentTime();
pacer.SetPacingRates(2 * kPacingRate, DataRate::Zero());
} else {
third_packet_time = time_controller.GetClock()->CurrentTime();
}
});
pacer.EnqueuePackets(GeneratePackets(RtpPacketMediaType::kVideo, 3));
time_controller.AdvanceTime(TimeDelta::Millis(500));
ASSERT_TRUE(third_packet_time.IsFinite());
EXPECT_NEAR((second_packet_time - first_packet_time).ms<double>(), 200.0,
1.0);
EXPECT_NEAR((third_packet_time - second_packet_time).ms<double>(), 100.0,
1.0);
}
TEST(TaskQueuePacedSenderTest, SendsAudioImmediately) {
GlobalSimulatedTimeController time_controller(Timestamp::Millis(1234));
MockPacketRouter packet_router;
TaskQueuePacedSenderForTest pacer(
time_controller.GetClock(), &packet_router,
/*event_log=*/nullptr,
/*field_trials=*/nullptr, time_controller.GetTaskQueueFactory(),
PacingController::kMinSleepTime);
const DataRate kPacingDataRate = DataRate::KilobitsPerSec(125);
const DataSize kPacketSize = DataSize::Bytes(kDefaultPacketSize);
const TimeDelta kPacketPacingTime = kPacketSize / kPacingDataRate;
pacer.SetPacingRates(kPacingDataRate, DataRate::Zero());
pacer.EnsureStarted();
// Add some initial video packets, only one should be sent.
EXPECT_CALL(packet_router, SendPacket);
pacer.EnqueuePackets(GeneratePackets(RtpPacketMediaType::kVideo, 10));
time_controller.AdvanceTime(TimeDelta::Zero());
::testing::Mock::VerifyAndClearExpectations(&packet_router);
// Advance time, but still before next packet should be sent.
time_controller.AdvanceTime(kPacketPacingTime / 2);
// Insert an audio packet, it should be sent immediately.
EXPECT_CALL(packet_router, SendPacket);
pacer.EnqueuePackets(GeneratePackets(RtpPacketMediaType::kAudio, 1));
time_controller.AdvanceTime(TimeDelta::Zero());
::testing::Mock::VerifyAndClearExpectations(&packet_router);
}
TEST(TaskQueuePacedSenderTest, SleepsDuringCoalscingWindow) {
const TimeDelta kCoalescingWindow = TimeDelta::Millis(5);
GlobalSimulatedTimeController time_controller(Timestamp::Millis(1234));
MockPacketRouter packet_router;
TaskQueuePacedSenderForTest pacer(
time_controller.GetClock(), &packet_router,
/*event_log=*/nullptr,
/*field_trials=*/nullptr, time_controller.GetTaskQueueFactory(),
kCoalescingWindow);
// Set rates so one packet adds one ms of buffer level.
const DataSize kPacketSize = DataSize::Bytes(kDefaultPacketSize);
const TimeDelta kPacketPacingTime = TimeDelta::Millis(1);
const DataRate kPacingDataRate = kPacketSize / kPacketPacingTime;
pacer.SetPacingRates(kPacingDataRate, DataRate::Zero());
pacer.EnsureStarted();
// Add 10 packets. The first should be sent immediately since the buffers
// are clear.
EXPECT_CALL(packet_router, SendPacket);
pacer.EnqueuePackets(GeneratePackets(RtpPacketMediaType::kVideo, 10));
time_controller.AdvanceTime(TimeDelta::Zero());
::testing::Mock::VerifyAndClearExpectations(&packet_router);
// Advance time to 1ms before the coalescing window ends. No packets should
// be sent.
EXPECT_CALL(packet_router, SendPacket).Times(0);
time_controller.AdvanceTime(kCoalescingWindow - TimeDelta::Millis(1));
// Advance time to where coalescing window ends. All packets that should
// have been sent up til now will be sent.
EXPECT_CALL(packet_router, SendPacket).Times(5);
time_controller.AdvanceTime(TimeDelta::Millis(1));
::testing::Mock::VerifyAndClearExpectations(&packet_router);
}
TEST(TaskQueuePacedSenderTest, ProbingOverridesCoalescingWindow) {
const TimeDelta kCoalescingWindow = TimeDelta::Millis(5);
GlobalSimulatedTimeController time_controller(Timestamp::Millis(1234));
MockPacketRouter packet_router;
TaskQueuePacedSenderForTest pacer(
time_controller.GetClock(), &packet_router,
/*event_log=*/nullptr,
/*field_trials=*/nullptr, time_controller.GetTaskQueueFactory(),
kCoalescingWindow);
// Set rates so one packet adds one ms of buffer level.
const DataSize kPacketSize = DataSize::Bytes(kDefaultPacketSize);
const TimeDelta kPacketPacingTime = TimeDelta::Millis(1);
const DataRate kPacingDataRate = kPacketSize / kPacketPacingTime;
pacer.SetPacingRates(kPacingDataRate, DataRate::Zero());
pacer.EnsureStarted();
// Add 10 packets. The first should be sent immediately since the buffers
// are clear. This will also trigger the probe to start.
EXPECT_CALL(packet_router, SendPacket).Times(AtLeast(1));
pacer.CreateProbeCluster(kPacingDataRate * 2, 17);
pacer.EnqueuePackets(GeneratePackets(RtpPacketMediaType::kVideo, 10));
time_controller.AdvanceTime(TimeDelta::Zero());
::testing::Mock::VerifyAndClearExpectations(&packet_router);
// Advance time to 1ms before the coalescing window ends. Packets should be
// flying.
EXPECT_CALL(packet_router, SendPacket).Times(AtLeast(1));
time_controller.AdvanceTime(kCoalescingWindow - TimeDelta::Millis(1));
}
TEST(TaskQueuePacedSenderTest, RespectedMinTimeBetweenStatsUpdates) {
const TimeDelta kCoalescingWindow = TimeDelta::Millis(5);
GlobalSimulatedTimeController time_controller(Timestamp::Millis(1234));
MockPacketRouter packet_router;
TaskQueuePacedSenderForTest pacer(
time_controller.GetClock(), &packet_router,
/*event_log=*/nullptr,
/*field_trials=*/nullptr, time_controller.GetTaskQueueFactory(),
kCoalescingWindow);
const DataRate kPacingDataRate = DataRate::KilobitsPerSec(300);
pacer.SetPacingRates(kPacingDataRate, DataRate::Zero());
pacer.EnsureStarted();
const TimeDelta kMinTimeBetweenStatsUpdates = TimeDelta::Millis(1);
// Nothing inserted, no stats updates yet.
EXPECT_EQ(pacer.num_stats_updates_, 0u);
// Insert one packet, stats should be updated.
pacer.EnqueuePackets(GeneratePackets(RtpPacketMediaType::kVideo, 1));
time_controller.AdvanceTime(TimeDelta::Zero());
EXPECT_EQ(pacer.num_stats_updates_, 1u);
// Advance time half of the min stats update interval, and trigger a
// refresh - stats should not be updated yet.
time_controller.AdvanceTime(kMinTimeBetweenStatsUpdates / 2);
pacer.EnqueuePackets({});
time_controller.AdvanceTime(TimeDelta::Zero());
EXPECT_EQ(pacer.num_stats_updates_, 1u);
// Advance time the next half, now stats update is triggered.
time_controller.AdvanceTime(kMinTimeBetweenStatsUpdates / 2);
pacer.EnqueuePackets({});
time_controller.AdvanceTime(TimeDelta::Zero());
EXPECT_EQ(pacer.num_stats_updates_, 2u);
}
TEST(TaskQueuePacedSenderTest, ThrottlesStatsUpdates) {
const TimeDelta kCoalescingWindow = TimeDelta::Millis(5);
GlobalSimulatedTimeController time_controller(Timestamp::Millis(1234));
MockPacketRouter packet_router;
TaskQueuePacedSenderForTest pacer(
time_controller.GetClock(), &packet_router,
/*event_log=*/nullptr,
/*field_trials=*/nullptr, time_controller.GetTaskQueueFactory(),
kCoalescingWindow);
// Set rates so one packet adds 10ms of buffer level.
const DataSize kPacketSize = DataSize::Bytes(kDefaultPacketSize);
const TimeDelta kPacketPacingTime = TimeDelta::Millis(10);
const DataRate kPacingDataRate = kPacketSize / kPacketPacingTime;
const TimeDelta kMinTimeBetweenStatsUpdates = TimeDelta::Millis(1);
const TimeDelta kMaxTimeBetweenStatsUpdates = TimeDelta::Millis(33);
// Nothing inserted, no stats updates yet.
size_t num_expected_stats_updates = 0;
EXPECT_EQ(pacer.num_stats_updates_, num_expected_stats_updates);
pacer.SetPacingRates(kPacingDataRate, DataRate::Zero());
pacer.EnsureStarted();
time_controller.AdvanceTime(kMinTimeBetweenStatsUpdates);
// Updating pacing rates refreshes stats.
EXPECT_EQ(pacer.num_stats_updates_, ++num_expected_stats_updates);
// Record time when we insert first packet, this triggers the scheduled
// stats updating.
Clock* const clock = time_controller.GetClock();
const Timestamp start_time = clock->CurrentTime();
while (clock->CurrentTime() - start_time <=
kMaxTimeBetweenStatsUpdates - kPacketPacingTime) {
// Enqueue packet, expect stats update.
pacer.EnqueuePackets(GeneratePackets(RtpPacketMediaType::kVideo, 1));
time_controller.AdvanceTime(TimeDelta::Zero());
EXPECT_EQ(pacer.num_stats_updates_, ++num_expected_stats_updates);
// Advance time to halfway through pacing time, expect another stats
// update.
time_controller.AdvanceTime(kPacketPacingTime / 2);
pacer.EnqueuePackets({});
time_controller.AdvanceTime(TimeDelta::Zero());
EXPECT_EQ(pacer.num_stats_updates_, ++num_expected_stats_updates);
// Advance time the rest of the way.
time_controller.AdvanceTime(kPacketPacingTime / 2);
}
// At this point, the pace queue is drained so there is no more intersting
// update to be made - but there is still as schduled task that should run
// |kMaxTimeBetweenStatsUpdates| after the first update.
time_controller.AdvanceTime(start_time + kMaxTimeBetweenStatsUpdates -
clock->CurrentTime());
EXPECT_EQ(pacer.num_stats_updates_, ++num_expected_stats_updates);
// Advance time a significant time - don't expect any more calls as stats
// updating does not happen when queue is drained.
time_controller.AdvanceTime(TimeDelta::Millis(400));
EXPECT_EQ(pacer.num_stats_updates_, num_expected_stats_updates);
}
TEST(TaskQueuePacedSenderTest, SchedulesProbeAtSetTime) {
ScopedFieldTrials trials("WebRTC-Bwe-ProbingBehavior/min_probe_delta:1ms/");
GlobalSimulatedTimeController time_controller(Timestamp::Millis(1234));
MockPacketRouter packet_router;
TaskQueuePacedSenderForTest pacer(
time_controller.GetClock(), &packet_router,
/*event_log=*/nullptr,
/*field_trials=*/nullptr, time_controller.GetTaskQueueFactory(),
PacingController::kMinSleepTime);
// Set rates so one packet adds 4ms of buffer level.
const DataSize kPacketSize = DataSize::Bytes(kDefaultPacketSize);
const TimeDelta kPacketPacingTime = TimeDelta::Millis(4);
const DataRate kPacingDataRate = kPacketSize / kPacketPacingTime;
pacer.SetPacingRates(kPacingDataRate, /*padding_rate=*/DataRate::Zero());
pacer.EnsureStarted();
EXPECT_CALL(packet_router, FetchFec).WillRepeatedly([]() {
return std::vector<std::unique_ptr<RtpPacketToSend>>();
});
EXPECT_CALL(packet_router, GeneratePadding(_))
.WillRepeatedly(
[](DataSize target_size) { return GeneratePadding(target_size); });
// Enqueue two packets, only the first is sent immediately and the next
// will be scheduled for sending in 4ms.
pacer.EnqueuePackets(GeneratePackets(RtpPacketMediaType::kVideo, 2));
const int kNotAProbe = PacedPacketInfo::kNotAProbe;
EXPECT_CALL(
packet_router,
SendPacket(_, ::testing::Field(&PacedPacketInfo::probe_cluster_id,
kNotAProbe)));
// Advance to less than 3ms before next packet send time.
time_controller.AdvanceTime(TimeDelta::Micros(1001));
// Trigger a probe at 4x the current pacing rate and insert the number of
// packets the probe needs.
const DataRate kProbeRate = 2 * kPacingDataRate;
const int kProbeClusterId = 1;
pacer.CreateProbeCluster(kProbeRate, kProbeClusterId);
// Expected size for each probe in a cluster is twice the expected bits
// sent during min_probe_delta.
// Expect one additional call since probe always starts with a small
const TimeDelta kProbeTimeDelta = TimeDelta::Millis(2);
const DataSize kProbeSize = kProbeRate * kProbeTimeDelta;
const size_t kNumPacketsInProbe =
(kProbeSize + kPacketSize - DataSize::Bytes(1)) / kPacketSize;
EXPECT_CALL(
packet_router,
SendPacket(_, ::testing::Field(&PacedPacketInfo::probe_cluster_id,
kProbeClusterId)))
.Times(kNumPacketsInProbe + 1);
pacer.EnqueuePackets(
GeneratePackets(RtpPacketMediaType::kVideo, kNumPacketsInProbe));
time_controller.AdvanceTime(TimeDelta::Zero());
// The pacer should have scheduled the next probe to be sent in
// kProbeTimeDelta. That there was existing scheduled call less than
// PacingController::kMinSleepTime before this should not matter.
EXPECT_CALL(
packet_router,
SendPacket(_, ::testing::Field(&PacedPacketInfo::probe_cluster_id,
kProbeClusterId)))
.Times(AtLeast(1));
time_controller.AdvanceTime(TimeDelta::Millis(2));
}
TEST(TaskQueuePacedSenderTest, NoMinSleepTimeWhenProbing) {
// Set min_probe_delta to be less than kMinSleepTime (1ms).
const TimeDelta kMinProbeDelta = TimeDelta::Micros(100);
ScopedFieldTrials trials(
"WebRTC-Bwe-ProbingBehavior/min_probe_delta:100us/");
GlobalSimulatedTimeController time_controller(Timestamp::Millis(1234));
MockPacketRouter packet_router;
TaskQueuePacedSenderForTest pacer(
time_controller.GetClock(), &packet_router,
/*event_log=*/nullptr,
/*field_trials=*/nullptr, time_controller.GetTaskQueueFactory(),
PacingController::kMinSleepTime);
// Set rates so one packet adds 4ms of buffer level.
const DataSize kPacketSize = DataSize::Bytes(kDefaultPacketSize);
const TimeDelta kPacketPacingTime = TimeDelta::Millis(4);
const DataRate kPacingDataRate = kPacketSize / kPacketPacingTime;
pacer.SetPacingRates(kPacingDataRate, /*padding_rate=*/DataRate::Zero());
pacer.EnsureStarted();
EXPECT_CALL(packet_router, FetchFec).WillRepeatedly([]() {
return std::vector<std::unique_ptr<RtpPacketToSend>>();
});
EXPECT_CALL(packet_router, GeneratePadding)
.WillRepeatedly(
[](DataSize target_size) { return GeneratePadding(target_size); });
// Set a high probe rate.
const int kProbeClusterId = 1;
DataRate kProbingRate = kPacingDataRate * 10;
pacer.CreateProbeCluster(kProbingRate, kProbeClusterId);
// Advance time less than PacingController::kMinSleepTime, probing packets
// for the first millisecond should be sent immediately. Min delta between
// probes is 2x 100us, meaning 4 times per ms we will get least one call to
// SendPacket().
DataSize data_sent = DataSize::Zero();
EXPECT_CALL(
packet_router,
SendPacket(_, ::testing::Field(&PacedPacketInfo::probe_cluster_id,
kProbeClusterId)))
.Times(AtLeast(4))
.WillRepeatedly([&](std::unique_ptr<RtpPacketToSend> packet,
const PacedPacketInfo&) {
data_sent +=
DataSize::Bytes(packet->payload_size() + packet->padding_size());
});
// Add one packet to kickstart probing, the rest will be padding packets.
pacer.EnqueuePackets(GeneratePackets(RtpPacketMediaType::kVideo, 1));
time_controller.AdvanceTime(kMinProbeDelta);
// Verify the amount of probing data sent.
// Probe always starts with a small (1 byte) padding packet that's not
// counted into the probe rate here.
EXPECT_EQ(data_sent,
kProbingRate * TimeDelta::Millis(1) + DataSize::Bytes(1));
}
TEST(TaskQueuePacedSenderTest, NoStatsUpdatesBeforeStart) {
const TimeDelta kCoalescingWindow = TimeDelta::Millis(5);
GlobalSimulatedTimeController time_controller(Timestamp::Millis(1234));
MockPacketRouter packet_router;
TaskQueuePacedSenderForTest pacer(
time_controller.GetClock(), &packet_router,
/*event_log=*/nullptr,
/*field_trials=*/nullptr, time_controller.GetTaskQueueFactory(),
kCoalescingWindow);
const DataRate kPacingDataRate = DataRate::KilobitsPerSec(300);
pacer.SetPacingRates(kPacingDataRate, DataRate::Zero());
const TimeDelta kMinTimeBetweenStatsUpdates = TimeDelta::Millis(1);
// Nothing inserted, no stats updates yet.
EXPECT_EQ(pacer.num_stats_updates_, 0u);
// Insert one packet, stats should not be updated.
pacer.EnqueuePackets(GeneratePackets(RtpPacketMediaType::kVideo, 1));
time_controller.AdvanceTime(TimeDelta::Zero());
EXPECT_EQ(pacer.num_stats_updates_, 0u);
// Advance time of the min stats update interval, and trigger a
// refresh - stats should not be updated still.
time_controller.AdvanceTime(kMinTimeBetweenStatsUpdates);
EXPECT_EQ(pacer.num_stats_updates_, 0u);
}
} // namespace test
} // namespace webrtc