webrtc/modules/congestion_controller/goog_cc/probe_controller_unittest.cc
Jonas Olsson 24923e8cfa Make some constants in the bitrate prober configurable.
This lets us change how many bytes and packets goes into the probes, as
well as some other things.

Bug: webrtc:10394
Change-Id: I26bb26a644e6f00366e9275228760c8744d63735
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/128424
Commit-Queue: Jonas Olsson <jonasolsson@webrtc.org>
Reviewed-by: Sebastian Jansson <srte@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#27312}
2019-03-27 13:50:35 +00:00

338 lines
14 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 <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 "modules/congestion_controller/goog_cc/probe_controller.h"
#include "rtc_base/logging.h"
#include "system_wrappers/include/clock.h"
#include "test/field_trial.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 ProbeControllerTest : public ::testing::Test {
protected:
ProbeControllerTest() : clock_(100000000L) {
probe_controller_.reset(
new ProbeController(&field_trial_config_, &mock_rtc_event_log));
}
~ProbeControllerTest() override {}
std::vector<ProbeClusterConfig> SetNetworkAvailable(bool available) {
NetworkAvailability msg;
msg.at_time = Timestamp::ms(NowMs());
msg.network_available = available;
return probe_controller_->OnNetworkAvailability(msg);
}
int64_t NowMs() { return clock_.TimeInMilliseconds(); }
FieldTrialBasedConfig field_trial_config_;
SimulatedClock clock_;
NiceMock<MockRtcEventLog> mock_rtc_event_log;
std::unique_ptr<ProbeController> probe_controller_;
};
TEST_F(ProbeControllerTest, InitiatesProbingAtStart) {
auto probes = probe_controller_->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, NowMs());
EXPECT_GE(probes.size(), 2u);
}
TEST_F(ProbeControllerTest, ProbeOnlyWhenNetworkIsUp) {
SetNetworkAvailable(false);
auto probes = probe_controller_->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, NowMs());
EXPECT_EQ(probes.size(), 0u);
probes = SetNetworkAvailable(true);
EXPECT_GE(probes.size(), 2u);
}
TEST_F(ProbeControllerTest, InitiatesProbingOnMaxBitrateIncrease) {
auto probes = probe_controller_->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, NowMs());
// Long enough to time out exponential probing.
clock_.AdvanceTimeMilliseconds(kExponentialProbingTimeoutMs);
probes = probe_controller_->SetEstimatedBitrate(kStartBitrateBps, NowMs());
probes = probe_controller_->Process(NowMs());
probes = probe_controller_->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps + 100, NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), kMaxBitrateBps + 100);
}
TEST_F(ProbeControllerTest, InitiatesProbingOnMaxBitrateIncreaseAtMaxBitrate) {
auto probes = probe_controller_->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, NowMs());
// Long enough to time out exponential probing.
clock_.AdvanceTimeMilliseconds(kExponentialProbingTimeoutMs);
probes = probe_controller_->SetEstimatedBitrate(kStartBitrateBps, NowMs());
probes = probe_controller_->Process(NowMs());
probes = probe_controller_->SetEstimatedBitrate(kMaxBitrateBps, NowMs());
probes = probe_controller_->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps + 100, NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), kMaxBitrateBps + 100);
}
TEST_F(ProbeControllerTest, TestExponentialProbing) {
auto probes = probe_controller_->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, NowMs());
// Repeated probe should only be sent when estimated bitrate climbs above
// 0.7 * 6 * kStartBitrateBps = 1260.
probes = probe_controller_->SetEstimatedBitrate(1000, NowMs());
EXPECT_EQ(probes.size(), 0u);
probes = probe_controller_->SetEstimatedBitrate(1800, NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), 2 * 1800);
}
TEST_F(ProbeControllerTest, TestExponentialProbingTimeout) {
auto probes = probe_controller_->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, NowMs());
// Advance far enough to cause a time out in waiting for probing result.
clock_.AdvanceTimeMilliseconds(kExponentialProbingTimeoutMs);
probes = probe_controller_->Process(NowMs());
probes = probe_controller_->SetEstimatedBitrate(1800, NowMs());
EXPECT_EQ(probes.size(), 0u);
}
TEST_F(ProbeControllerTest, RequestProbeInAlr) {
auto probes = probe_controller_->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, NowMs());
EXPECT_GE(probes.size(), 2u);
probes = probe_controller_->SetEstimatedBitrate(500, NowMs());
probe_controller_->SetAlrStartTimeMs(clock_.TimeInMilliseconds());
clock_.AdvanceTimeMilliseconds(kAlrProbeInterval + 1);
probes = probe_controller_->Process(NowMs());
probes = probe_controller_->SetEstimatedBitrate(250, NowMs());
probes = probe_controller_->RequestProbe(NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), 0.85 * 500);
}
TEST_F(ProbeControllerTest, RequestProbeWhenAlrEndedRecently) {
auto probes = probe_controller_->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, NowMs());
EXPECT_EQ(probes.size(), 2u);
probes = probe_controller_->SetEstimatedBitrate(500, NowMs());
probe_controller_->SetAlrStartTimeMs(absl::nullopt);
clock_.AdvanceTimeMilliseconds(kAlrProbeInterval + 1);
probes = probe_controller_->Process(NowMs());
probes = probe_controller_->SetEstimatedBitrate(250, NowMs());
probe_controller_->SetAlrEndedTimeMs(clock_.TimeInMilliseconds());
clock_.AdvanceTimeMilliseconds(kAlrEndedTimeoutMs - 1);
probes = probe_controller_->RequestProbe(NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), 0.85 * 500);
}
TEST_F(ProbeControllerTest, RequestProbeWhenAlrNotEndedRecently) {
auto probes = probe_controller_->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, NowMs());
EXPECT_EQ(probes.size(), 2u);
probes = probe_controller_->SetEstimatedBitrate(500, NowMs());
probe_controller_->SetAlrStartTimeMs(absl::nullopt);
clock_.AdvanceTimeMilliseconds(kAlrProbeInterval + 1);
probes = probe_controller_->Process(NowMs());
probes = probe_controller_->SetEstimatedBitrate(250, NowMs());
probe_controller_->SetAlrEndedTimeMs(clock_.TimeInMilliseconds());
clock_.AdvanceTimeMilliseconds(kAlrEndedTimeoutMs + 1);
probes = probe_controller_->RequestProbe(NowMs());
EXPECT_EQ(probes.size(), 0u);
}
TEST_F(ProbeControllerTest, RequestProbeWhenBweDropNotRecent) {
auto probes = probe_controller_->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, NowMs());
EXPECT_EQ(probes.size(), 2u);
probes = probe_controller_->SetEstimatedBitrate(500, NowMs());
probe_controller_->SetAlrStartTimeMs(clock_.TimeInMilliseconds());
clock_.AdvanceTimeMilliseconds(kAlrProbeInterval + 1);
probes = probe_controller_->Process(NowMs());
probes = probe_controller_->SetEstimatedBitrate(250, NowMs());
clock_.AdvanceTimeMilliseconds(kBitrateDropTimeoutMs + 1);
probes = probe_controller_->RequestProbe(NowMs());
EXPECT_EQ(probes.size(), 0u);
}
TEST_F(ProbeControllerTest, PeriodicProbing) {
probe_controller_->EnablePeriodicAlrProbing(true);
auto probes = probe_controller_->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, NowMs());
EXPECT_EQ(probes.size(), 2u);
probes = probe_controller_->SetEstimatedBitrate(500, NowMs());
int64_t start_time = clock_.TimeInMilliseconds();
// Expect the controller to send a new probe after 5s has passed.
probe_controller_->SetAlrStartTimeMs(start_time);
clock_.AdvanceTimeMilliseconds(5000);
probes = probe_controller_->Process(NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), 1000);
probes = probe_controller_->SetEstimatedBitrate(500, NowMs());
// The following probe should be sent at 10s into ALR.
probe_controller_->SetAlrStartTimeMs(start_time);
clock_.AdvanceTimeMilliseconds(4000);
probes = probe_controller_->Process(NowMs());
probes = probe_controller_->SetEstimatedBitrate(500, NowMs());
EXPECT_EQ(probes.size(), 0u);
probe_controller_->SetAlrStartTimeMs(start_time);
clock_.AdvanceTimeMilliseconds(1000);
probes = probe_controller_->Process(NowMs());
EXPECT_EQ(probes.size(), 1u);
probes = probe_controller_->SetEstimatedBitrate(500, NowMs());
EXPECT_EQ(probes.size(), 0u);
}
TEST_F(ProbeControllerTest, PeriodicProbingAfterReset) {
probe_controller_.reset(
new ProbeController(&field_trial_config_, &mock_rtc_event_log));
int64_t alr_start_time = clock_.TimeInMilliseconds();
probe_controller_->SetAlrStartTimeMs(alr_start_time);
probe_controller_->EnablePeriodicAlrProbing(true);
auto probes = probe_controller_->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, NowMs());
probe_controller_->Reset(NowMs());
clock_.AdvanceTimeMilliseconds(10000);
probes = probe_controller_->Process(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, NowMs());
EXPECT_EQ(probes.size(), 2u);
// Make sure we use |kStartBitrateBps| as the estimated bitrate
// until SetEstimatedBitrate is called with an updated estimate.
clock_.AdvanceTimeMilliseconds(10000);
probes = probe_controller_->Process(NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), kStartBitrateBps * 2);
}
TEST_F(ProbeControllerTest, TestExponentialProbingOverflow) {
const int64_t kMbpsMultiplier = 1000000;
auto probes = probe_controller_->SetBitrates(
kMinBitrateBps, 10 * kMbpsMultiplier, 100 * kMbpsMultiplier, NowMs());
// Verify that probe bitrate is capped at the specified max bitrate.
probes =
probe_controller_->SetEstimatedBitrate(60 * kMbpsMultiplier, 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, NowMs());
EXPECT_EQ(probes.size(), 0u);
}
TEST_F(ProbeControllerTest, TestAllocatedBitrateCap) {
const int64_t kMbpsMultiplier = 1000000;
const int64_t kMaxBitrateBps = 100 * kMbpsMultiplier;
auto probes = probe_controller_->SetBitrates(
kMinBitrateBps, 10 * kMbpsMultiplier, kMaxBitrateBps, NowMs());
// Configure ALR for periodic probing.
probe_controller_->EnablePeriodicAlrProbing(true);
int64_t alr_start_time = clock_.TimeInMilliseconds();
probe_controller_->SetAlrStartTimeMs(alr_start_time);
int64_t estimated_bitrate_bps = kMaxBitrateBps / 10;
probes =
probe_controller_->SetEstimatedBitrate(estimated_bitrate_bps, 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, NowMs());
EXPECT_TRUE(probes.empty()); // No probe since lower than current max.
// Probes such as ALR capped at 2x the max allocation limit.
clock_.AdvanceTimeMilliseconds(5000);
probes = probe_controller_->Process(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, NowMs()).empty());
clock_.AdvanceTimeMilliseconds(5000);
probes = probe_controller_->Process(NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), estimated_bitrate_bps * 2);
}
TEST_F(ProbeControllerTest, ConfigurableProbingFieldTrial) {
test::ScopedFieldTrials trials(
"WebRTC-Bwe-ProbingConfiguration/"
"p1:2,p2:5,step_size:3,further_probe_threshold:0.8/");
probe_controller_.reset(
new ProbeController(&field_trial_config_, &mock_rtc_event_log));
auto probes = probe_controller_->SetBitrates(kMinBitrateBps, kStartBitrateBps,
kMaxBitrateBps, 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, NowMs());
EXPECT_EQ(probes.size(), 0u);
probes = probe_controller_->SetEstimatedBitrate(1250, NowMs());
EXPECT_EQ(probes.size(), 1u);
EXPECT_EQ(probes[0].target_data_rate.bps(), 3 * 1250);
}
} // namespace test
} // namespace webrtc