webrtc/modules/congestion_controller/goog_cc/probe_controller_unittest.cc
Per Kjellander 88af20356f Use ProbeClusterConfig in BitrateProber from GoogCC
Instead of using field trials in BitrateProber for probe duration, use values provided in ProbeClusterConfig from GoogCC.
Field trials are instead read in ProbeController.

To avoid having to do a thread jump for every ProbeClusterConfig, RtpPacketPacer interface is changed to RtpPacketPacer::CreateProbeClusters(std::vector<ProbeClusterConfig>

Deprecates field trial  "WebRTC-Bwe-ProbingConfiguration"

Change-Id: I3991e4b54770601855a3af2d6a16678f11d41c31
Bug: webrtc:14027
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/261265
Reviewed-by: Erik Språng <sprang@webrtc.org>
Commit-Queue: Per Kjellander <perkj@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#36911}
2022-05-17 12:29:25 +00:00

449 lines
18 KiB
C++

/*
* Copyright (c) 2016 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/goog_cc/probe_controller.h"
#include <memory>
#include "api/transport/field_trial_based_config.h"
#include "api/transport/network_types.h"
#include "api/units/data_rate.h"
#include "api/units/timestamp.h"
#include "logging/rtc_event_log/mock/mock_rtc_event_log.h"
#include "rtc_base/logging.h"
#include "system_wrappers/include/clock.h"
#include "test/explicit_key_value_config.h"
#include "test/gmock.h"
#include "test/gtest.h"
using ::testing::_;
using ::testing::AtLeast;
using ::testing::Field;
using ::testing::Matcher;
using ::testing::NiceMock;
using ::testing::Return;
namespace webrtc {
namespace test {
namespace {
constexpr int kMinBitrateBps = 100;
constexpr int kStartBitrateBps = 300;
constexpr int kMaxBitrateBps = 10000;
constexpr int kExponentialProbingTimeoutMs = 5000;
constexpr int kAlrProbeInterval = 5000;
constexpr int kAlrEndedTimeoutMs = 3000;
constexpr int kBitrateDropTimeoutMs = 5000;
} // namespace
class ProbeControllerFixture {
public:
explicit ProbeControllerFixture(absl::string_view field_trials = "")
: field_trial_config_(field_trials), clock_(100000000L) {}
std::unique_ptr<ProbeController> CreateController() {
return std::make_unique<ProbeController>(&field_trial_config_,
&mock_rtc_event_log);
}
Timestamp CurrentTime() { return clock_.CurrentTime(); }
int64_t NowMs() { return clock_.TimeInMilliseconds(); }
void AdvanceTimeMilliseconds(int64_t delta_ms) {
clock_.AdvanceTimeMilliseconds(delta_ms);
}
ExplicitKeyValueConfig field_trial_config_;
SimulatedClock clock_;
NiceMock<MockRtcEventLog> mock_rtc_event_log;
};
TEST(ProbeControllerTest, InitiatesProbingAtStart) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
auto probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, fixture.NowMs());
EXPECT_GE(probes.size(), 2u);
}
TEST(ProbeControllerTest, SetsDefaultTargetDurationAndTargetProbeCount) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
std::vector<ProbeClusterConfig> probes = probe_controller->SetBitrates(
kMinBitrateBps, kStartBitrateBps, kMaxBitrateBps, fixture.NowMs());
ASSERT_GE(probes.size(), 2u);
EXPECT_EQ(probes[0].target_duration, TimeDelta::Millis(15));
EXPECT_EQ(probes[0].target_probe_count, 5);
}
TEST(ProbeControllerTest,
FieldTrialsOverrideDefaultTargetDurationAndTargetProbeCount) {
ProbeControllerFixture fixture(
"WebRTC-Bwe-ProbingBehavior/"
"min_probe_packets_sent:2,min_probe_duration:123ms/");
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
std::vector<ProbeClusterConfig> probes = probe_controller->SetBitrates(
kMinBitrateBps, kStartBitrateBps, kMaxBitrateBps, fixture.NowMs());
ASSERT_GE(probes.size(), 2u);
EXPECT_EQ(probes[0].target_duration, TimeDelta::Millis(123));
EXPECT_EQ(probes[0].target_probe_count, 2);
}
TEST(ProbeControllerTest, ProbeOnlyWhenNetworkIsUp) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
auto probes = probe_controller->OnNetworkAvailability(
{.at_time = fixture.CurrentTime(), .network_available = false});
probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, fixture.NowMs());
EXPECT_EQ(probes.size(), 0u);
probes = probe_controller->OnNetworkAvailability(
{.at_time = fixture.CurrentTime(), .network_available = true});
EXPECT_GE(probes.size(), 2u);
}
TEST(ProbeControllerTest, InitiatesProbingOnMaxBitrateIncrease) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
auto probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, fixture.NowMs());
// Long enough to time out exponential probing.
fixture.AdvanceTimeMilliseconds(kExponentialProbingTimeoutMs);
probes =
probe_controller->SetEstimatedBitrate(kStartBitrateBps, fixture.NowMs());
probes = probe_controller->Process(fixture.NowMs());
probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps + 100, fixture.NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), kMaxBitrateBps + 100);
}
TEST(ProbeControllerTest, ProbesOnMaxBitrateIncreaseOnlyWhenInAlr) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
auto probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, fixture.NowMs());
probes = probe_controller->SetEstimatedBitrate(kMaxBitrateBps - 1,
fixture.NowMs());
// Wait long enough to time out exponential probing.
fixture.AdvanceTimeMilliseconds(kExponentialProbingTimeoutMs);
probes = probe_controller->Process(fixture.NowMs());
EXPECT_EQ(probes.size(), 0u);
// Probe when in alr.
probe_controller->SetAlrStartTimeMs(fixture.NowMs());
probes = probe_controller->OnMaxTotalAllocatedBitrate(kMaxBitrateBps + 1,
fixture.NowMs());
EXPECT_EQ(probes.size(), 2u);
// Do not probe when not in alr.
probe_controller->SetAlrStartTimeMs(absl::nullopt);
probes = probe_controller->OnMaxTotalAllocatedBitrate(kMaxBitrateBps + 2,
fixture.NowMs());
EXPECT_TRUE(probes.empty());
}
TEST(ProbeControllerTest, InitiatesProbingOnMaxBitrateIncreaseAtMaxBitrate) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
auto probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, fixture.NowMs());
// Long enough to time out exponential probing.
fixture.AdvanceTimeMilliseconds(kExponentialProbingTimeoutMs);
probes =
probe_controller->SetEstimatedBitrate(kStartBitrateBps, fixture.NowMs());
probes = probe_controller->Process(fixture.NowMs());
probes =
probe_controller->SetEstimatedBitrate(kMaxBitrateBps, fixture.NowMs());
probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps + 100, fixture.NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), kMaxBitrateBps + 100);
}
TEST(ProbeControllerTest, TestExponentialProbing) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
auto probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, fixture.NowMs());
// Repeated probe should only be sent when estimated bitrate climbs above
// 0.7 * 6 * kStartBitrateBps = 1260.
probes = probe_controller->SetEstimatedBitrate(1000, fixture.NowMs());
EXPECT_EQ(probes.size(), 0u);
probes = probe_controller->SetEstimatedBitrate(1800, fixture.NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), 2 * 1800);
}
TEST(ProbeControllerTest, TestExponentialProbingTimeout) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
auto probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, fixture.NowMs());
// Advance far enough to cause a time out in waiting for probing result.
fixture.AdvanceTimeMilliseconds(kExponentialProbingTimeoutMs);
probes = probe_controller->Process(fixture.NowMs());
probes = probe_controller->SetEstimatedBitrate(1800, fixture.NowMs());
EXPECT_EQ(probes.size(), 0u);
}
TEST(ProbeControllerTest, RequestProbeInAlr) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
auto probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, fixture.NowMs());
EXPECT_GE(probes.size(), 2u);
probes = probe_controller->SetEstimatedBitrate(500, fixture.NowMs());
probe_controller->SetAlrStartTimeMs(fixture.NowMs());
fixture.AdvanceTimeMilliseconds(kAlrProbeInterval + 1);
probes = probe_controller->Process(fixture.NowMs());
probes = probe_controller->SetEstimatedBitrate(250, fixture.NowMs());
probes = probe_controller->RequestProbe(fixture.NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), 0.85 * 500);
}
TEST(ProbeControllerTest, RequestProbeWhenAlrEndedRecently) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
auto probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, fixture.NowMs());
EXPECT_EQ(probes.size(), 2u);
probes = probe_controller->SetEstimatedBitrate(500, fixture.NowMs());
probe_controller->SetAlrStartTimeMs(absl::nullopt);
fixture.AdvanceTimeMilliseconds(kAlrProbeInterval + 1);
probes = probe_controller->Process(fixture.NowMs());
probes = probe_controller->SetEstimatedBitrate(250, fixture.NowMs());
probe_controller->SetAlrEndedTimeMs(fixture.NowMs());
fixture.AdvanceTimeMilliseconds(kAlrEndedTimeoutMs - 1);
probes = probe_controller->RequestProbe(fixture.NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), 0.85 * 500);
}
TEST(ProbeControllerTest, RequestProbeWhenAlrNotEndedRecently) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
auto probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, fixture.NowMs());
EXPECT_EQ(probes.size(), 2u);
probes = probe_controller->SetEstimatedBitrate(500, fixture.NowMs());
probe_controller->SetAlrStartTimeMs(absl::nullopt);
fixture.AdvanceTimeMilliseconds(kAlrProbeInterval + 1);
probes = probe_controller->Process(fixture.NowMs());
probes = probe_controller->SetEstimatedBitrate(250, fixture.NowMs());
probe_controller->SetAlrEndedTimeMs(fixture.NowMs());
fixture.AdvanceTimeMilliseconds(kAlrEndedTimeoutMs + 1);
probes = probe_controller->RequestProbe(fixture.NowMs());
EXPECT_EQ(probes.size(), 0u);
}
TEST(ProbeControllerTest, RequestProbeWhenBweDropNotRecent) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
auto probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, fixture.NowMs());
EXPECT_EQ(probes.size(), 2u);
probes = probe_controller->SetEstimatedBitrate(500, fixture.NowMs());
probe_controller->SetAlrStartTimeMs(fixture.NowMs());
fixture.AdvanceTimeMilliseconds(kAlrProbeInterval + 1);
probes = probe_controller->Process(fixture.NowMs());
probes = probe_controller->SetEstimatedBitrate(250, fixture.NowMs());
fixture.AdvanceTimeMilliseconds(kBitrateDropTimeoutMs + 1);
probes = probe_controller->RequestProbe(fixture.NowMs());
EXPECT_EQ(probes.size(), 0u);
}
TEST(ProbeControllerTest, PeriodicProbing) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
probe_controller->EnablePeriodicAlrProbing(true);
auto probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, fixture.NowMs());
EXPECT_EQ(probes.size(), 2u);
probes = probe_controller->SetEstimatedBitrate(500, fixture.NowMs());
int64_t start_time = fixture.NowMs();
// Expect the controller to send a new probe after 5s has passed.
probe_controller->SetAlrStartTimeMs(start_time);
fixture.AdvanceTimeMilliseconds(5000);
probes = probe_controller->Process(fixture.NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), 1000);
probes = probe_controller->SetEstimatedBitrate(500, fixture.NowMs());
// The following probe should be sent at 10s into ALR.
probe_controller->SetAlrStartTimeMs(start_time);
fixture.AdvanceTimeMilliseconds(4000);
probes = probe_controller->Process(fixture.NowMs());
probes = probe_controller->SetEstimatedBitrate(500, fixture.NowMs());
EXPECT_EQ(probes.size(), 0u);
probe_controller->SetAlrStartTimeMs(start_time);
fixture.AdvanceTimeMilliseconds(1000);
probes = probe_controller->Process(fixture.NowMs());
EXPECT_EQ(probes.size(), 1u);
probes = probe_controller->SetEstimatedBitrate(500, fixture.NowMs());
EXPECT_EQ(probes.size(), 0u);
}
TEST(ProbeControllerTest, PeriodicProbingAfterReset) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
int64_t alr_start_time = fixture.NowMs();
probe_controller->SetAlrStartTimeMs(alr_start_time);
probe_controller->EnablePeriodicAlrProbing(true);
auto probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, fixture.NowMs());
probe_controller->Reset(fixture.NowMs());
fixture.AdvanceTimeMilliseconds(10000);
probes = probe_controller->Process(fixture.NowMs());
// Since bitrates are not yet set, no probe is sent event though we are in ALR
// mode.
EXPECT_EQ(probes.size(), 0u);
probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, fixture.NowMs());
EXPECT_EQ(probes.size(), 2u);
// Make sure we use `kStartBitrateBps` as the estimated bitrate
// until SetEstimatedBitrate is called with an updated estimate.
fixture.AdvanceTimeMilliseconds(10000);
probes = probe_controller->Process(fixture.NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), kStartBitrateBps * 2);
}
TEST(ProbeControllerTest, TestExponentialProbingOverflow) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
const int64_t kMbpsMultiplier = 1000000;
auto probes =
probe_controller->SetBitrates(kMinBitrateBps, 10 * kMbpsMultiplier,
100 * kMbpsMultiplier, fixture.NowMs());
// Verify that probe bitrate is capped at the specified max bitrate.
probes = probe_controller->SetEstimatedBitrate(60 * kMbpsMultiplier,
fixture.NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), 100 * kMbpsMultiplier);
// Verify that repeated probes aren't sent.
probes = probe_controller->SetEstimatedBitrate(100 * kMbpsMultiplier,
fixture.NowMs());
EXPECT_EQ(probes.size(), 0u);
}
TEST(ProbeControllerTest, TestAllocatedBitrateCap) {
ProbeControllerFixture fixture;
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
const int64_t kMbpsMultiplier = 1000000;
const int64_t kMaxBitrateBps = 100 * kMbpsMultiplier;
auto probes = probe_controller->SetBitrates(
kMinBitrateBps, 10 * kMbpsMultiplier, kMaxBitrateBps, fixture.NowMs());
// Configure ALR for periodic probing.
probe_controller->EnablePeriodicAlrProbing(true);
int64_t alr_start_time = fixture.NowMs();
probe_controller->SetAlrStartTimeMs(alr_start_time);
int64_t estimated_bitrate_bps = kMaxBitrateBps / 10;
probes = probe_controller->SetEstimatedBitrate(estimated_bitrate_bps,
fixture.NowMs());
// Set a max allocated bitrate below the current estimate.
int64_t max_allocated_bps = estimated_bitrate_bps - 1 * kMbpsMultiplier;
probes = probe_controller->OnMaxTotalAllocatedBitrate(max_allocated_bps,
fixture.NowMs());
EXPECT_TRUE(probes.empty()); // No probe since lower than current max.
// Probes such as ALR capped at 2x the max allocation limit.
fixture.AdvanceTimeMilliseconds(5000);
probes = probe_controller->Process(fixture.NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), 2 * max_allocated_bps);
// Remove allocation limit.
EXPECT_TRUE(
probe_controller->OnMaxTotalAllocatedBitrate(0, fixture.NowMs()).empty());
fixture.AdvanceTimeMilliseconds(5000);
probes = probe_controller->Process(fixture.NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), estimated_bitrate_bps * 2);
}
TEST(ProbeControllerTest, ConfigurableProbingFieldTrial) {
ProbeControllerFixture fixture(
"WebRTC-Bwe-ProbingConfiguration/"
"p1:2,p2:5,step_size:3,further_probe_threshold:0.8,"
"alloc_p1:2,alloc_p2/");
std::unique_ptr<ProbeController> probe_controller =
fixture.CreateController();
auto probes = probe_controller->SetBitrates(kMinBitrateBps, kStartBitrateBps,
5000000, fixture.NowMs());
EXPECT_EQ(probes.size(), 2u);
EXPECT_EQ(probes[0].target_data_rate.bps(), 600);
EXPECT_EQ(probes[1].target_data_rate.bps(), 1500);
// Repeated probe should only be sent when estimated bitrate climbs above
// 0.8 * 5 * kStartBitrateBps = 1200.
probes = probe_controller->SetEstimatedBitrate(1100, fixture.NowMs());
EXPECT_EQ(probes.size(), 0u);
probes = probe_controller->SetEstimatedBitrate(1250, fixture.NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), 3 * 1250);
fixture.AdvanceTimeMilliseconds(5000);
probes = probe_controller->Process(fixture.NowMs());
probe_controller->SetAlrStartTimeMs(fixture.NowMs());
probes =
probe_controller->OnMaxTotalAllocatedBitrate(200000, fixture.NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), 400000);
}
} // namespace test
} // namespace webrtc