| // Copyright 2018 The Chromium Authors |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "chrome/browser/metrics/perf/profile_provider_chromeos.h" |
| |
| #include <stdint.h> |
| |
| #include <memory> |
| #include <string> |
| #include <utility> |
| #include <vector> |
| |
| #include "base/test/bind.h" |
| #include "base/test/power_monitor_test.h" |
| #include "base/test/scoped_feature_list.h" |
| #include "base/test/task_environment.h" |
| #include "base/time/time.h" |
| #include "chrome/browser/metrics/perf/metric_collector.h" |
| #include "chrome/browser/metrics/perf/metric_provider.h" |
| #include "chrome/browser/metrics/perf/windowed_incognito_observer.h" |
| #include "chromeos/ash/components/login/login_state/login_state.h" |
| #include "content/public/browser/browser_task_traits.h" |
| #include "content/public/browser/browser_thread.h" |
| #include "content/public/test/browser_task_environment.h" |
| #include "testing/gtest/include/gtest/gtest.h" |
| #include "third_party/metrics_proto/sampled_profile.pb.h" |
| |
| namespace metrics { |
| |
| namespace { |
| |
| // Returns sample PerfDataProtos with custom timestamps. The contents don't have |
| // to make sense. They just need to constitute a semantically valid protobuf. |
| // |proto| is an output parameter that will contain the created protobuf. |
| PerfDataProto GetExamplePerfDataProto(int tstamp_sec) { |
| PerfDataProto proto; |
| proto.set_timestamp_sec(tstamp_sec); // Time since epoch in seconds. |
| |
| PerfDataProto_PerfFileAttr* file_attr = proto.add_file_attrs(); |
| file_attr->add_ids(61); |
| file_attr->add_ids(62); |
| file_attr->add_ids(63); |
| |
| PerfDataProto_PerfEventAttr* attr = file_attr->mutable_attr(); |
| attr->set_type(1); |
| attr->set_size(2); |
| attr->set_config(3); |
| attr->set_sample_period(4); |
| attr->set_sample_freq(5); |
| |
| PerfDataProto_PerfEventStats* stats = proto.mutable_stats(); |
| stats->set_num_events_read(100); |
| stats->set_num_sample_events(200); |
| stats->set_num_mmap_events(300); |
| stats->set_num_fork_events(400); |
| stats->set_num_exit_events(500); |
| |
| return proto; |
| } |
| |
| // Custome metric collectors to register with the profile provider for testing. |
| template <int TSTAMP> |
| class TestMetricCollector : public internal::MetricCollector { |
| public: |
| TestMetricCollector() : TestMetricCollector(CollectionParams()) {} |
| explicit TestMetricCollector(const CollectionParams& collection_params) |
| : internal::MetricCollector("UMA.CWP.TestData", collection_params) {} |
| |
| TestMetricCollector(const TestMetricCollector&) = delete; |
| TestMetricCollector& operator=(const TestMetricCollector&) = delete; |
| |
| const char* ToolName() const override { return "test"; } |
| base::WeakPtr<internal::MetricCollector> GetWeakPtr() override { |
| return weak_factory_.GetWeakPtr(); |
| } |
| |
| void CollectProfile( |
| std::unique_ptr<SampledProfile> sampled_profile) override { |
| PerfDataProto perf_data_proto = GetExamplePerfDataProto(TSTAMP); |
| // Create an incognito observer to test initialization on the UI thread. |
| auto observer = WindowedIncognitoMonitor::CreateObserver(); |
| if (!observer->IncognitoActive()) { |
| SaveSerializedPerfProto(std::move(sampled_profile), |
| perf_data_proto.SerializeAsString()); |
| } |
| } |
| |
| private: |
| base::WeakPtrFactory<TestMetricCollector> weak_factory_{this}; |
| }; |
| |
| const base::TimeDelta kPeriodicCollectionInterval = base::Hours(1); |
| const base::TimeDelta kMaxCollectionDelay = base::Seconds(1); |
| |
| // Allows access to some private methods for testing. |
| class TestProfileProvider : public ProfileProvider { |
| public: |
| TestProfileProvider() { |
| // Add a couple of metric collectors. We differentiate between them using |
| // different time stamps for profiles. Set sampling factors for triggers |
| // to 1, so we always trigger collection. |
| CollectionParams test_params; |
| test_params.resume_from_suspend.sampling_factor = 1; |
| test_params.resume_from_suspend.max_collection_delay = kMaxCollectionDelay; |
| test_params.restore_session.sampling_factor = 1; |
| test_params.restore_session.max_collection_delay = kMaxCollectionDelay; |
| test_params.periodic_interval = kPeriodicCollectionInterval; |
| |
| collectors_.clear(); |
| collectors_.push_back(std::make_unique<MetricProvider>( |
| std::make_unique<TestMetricCollector<100>>(test_params), nullptr)); |
| collectors_.push_back(std::make_unique<MetricProvider>( |
| std::make_unique<TestMetricCollector<200>>(test_params), nullptr)); |
| } |
| |
| using ProfileProvider::collectors_; |
| using ProfileProvider::jank_monitor; |
| using ProfileProvider::jankiness_collection_min_interval; |
| using ProfileProvider::LoggedInStateChanged; |
| using ProfileProvider::OnJankStarted; |
| using ProfileProvider::OnSessionRestoreDone; |
| using ProfileProvider::SuspendDone; |
| |
| TestProfileProvider(const TestProfileProvider&) = delete; |
| TestProfileProvider& operator=(const TestProfileProvider&) = delete; |
| }; |
| |
| void ExpectTwoStoredPerfProfiles( |
| const std::vector<SampledProfile>& stored_profiles, |
| SampledProfile_TriggerEvent want_trigger_type, |
| ThermalState want_thermal_state_type, |
| int want_speed_limit) { |
| ASSERT_EQ(2U, stored_profiles.size()); |
| // Both profiles must be of the given type and include perf data. |
| const SampledProfile& profile1 = stored_profiles[0]; |
| const SampledProfile& profile2 = stored_profiles[1]; |
| EXPECT_EQ(want_trigger_type, profile1.trigger_event()); |
| ASSERT_TRUE(profile1.has_perf_data()); |
| EXPECT_EQ(want_trigger_type, profile2.trigger_event()); |
| ASSERT_TRUE(profile2.has_perf_data()); |
| // Both profiles must include the given thermal state, |
| EXPECT_EQ(want_thermal_state_type, profile1.thermal_state()); |
| EXPECT_EQ(want_thermal_state_type, profile2.thermal_state()); |
| // ... and CPU speed limit. |
| EXPECT_EQ(want_speed_limit, profile1.cpu_speed_limit_percent()); |
| EXPECT_EQ(want_speed_limit, profile2.cpu_speed_limit_percent()); |
| |
| // We must have received a profile from each of the collectors. |
| EXPECT_EQ(100u, profile1.perf_data().timestamp_sec()); |
| EXPECT_EQ(200u, profile2.perf_data().timestamp_sec()); |
| } |
| |
| } // namespace |
| |
| class ProfileProviderTest : public testing::Test { |
| public: |
| ProfileProviderTest() |
| : task_environment_(base::test::TaskEnvironment::TimeSource::MOCK_TIME) {} |
| |
| ProfileProviderTest(const ProfileProviderTest&) = delete; |
| ProfileProviderTest& operator=(const ProfileProviderTest&) = delete; |
| |
| void SetUp() override { |
| // ProfileProvider requires ash::LoginState and |
| // chromeos::PowerManagerClient to be initialized. |
| chromeos::PowerManagerClient::InitializeFake(); |
| ash::LoginState::Initialize(); |
| test_power_monitor_source_.GenerateThermalThrottlingEvent( |
| base::PowerThermalObserver::DeviceThermalState::kNominal); |
| |
| profile_provider_ = std::make_unique<TestProfileProvider>(); |
| profile_provider_->Init(); |
| } |
| |
| void TearDown() override { |
| profile_provider_.reset(); |
| ash::LoginState::Shutdown(); |
| chromeos::PowerManagerClient::Shutdown(); |
| } |
| |
| protected: |
| // task_environment_ must be the first member (or at least before |
| // any member that cares about tasks) to be initialized first and destroyed |
| // last. |
| content::BrowserTaskEnvironment task_environment_; |
| base::test::ScopedPowerMonitorTestSource test_power_monitor_source_; |
| std::unique_ptr<TestProfileProvider> profile_provider_; |
| }; |
| |
| TEST_F(ProfileProviderTest, CheckSetup) { |
| EXPECT_EQ(2U, profile_provider_->collectors_.size()); |
| |
| // No profiles should be collected on start. |
| std::vector<SampledProfile> stored_profiles; |
| EXPECT_FALSE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| EXPECT_TRUE(stored_profiles.empty()); |
| } |
| |
| TEST_F(ProfileProviderTest, UserLoginLogout) { |
| // No user is logged in, so no collection is scheduled to run. |
| task_environment_.FastForwardBy(kPeriodicCollectionInterval); |
| |
| std::vector<SampledProfile> stored_profiles; |
| EXPECT_FALSE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| EXPECT_TRUE(stored_profiles.empty()); |
| |
| // Simulate a user log in, which should activate periodic collection for all |
| // collectors. |
| ash::LoginState::Get()->SetLoggedInState( |
| ash::LoginState::LOGGED_IN_ACTIVE, |
| ash::LoginState::LOGGED_IN_USER_REGULAR); |
| |
| // Run all pending tasks. SetLoggedInState has activated timers for periodic |
| // collection causing timer based pending tasks. |
| task_environment_.FastForwardBy(kPeriodicCollectionInterval); |
| // We should find two profiles, one for each collector. |
| EXPECT_TRUE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| ExpectTwoStoredPerfProfiles( |
| stored_profiles, SampledProfile::PERIODIC_COLLECTION, |
| THERMAL_STATE_NOMINAL, base::PowerThermalObserver::kSpeedLimitMax); |
| |
| // Periodic collection is deactivated when user logs out. Simulate a user |
| // logout event. |
| ash::LoginState::Get()->SetLoggedInState( |
| ash::LoginState::LOGGED_IN_NONE, ash::LoginState::LOGGED_IN_USER_NONE); |
| // Run all pending tasks. |
| task_environment_.FastForwardBy(kPeriodicCollectionInterval); |
| // We should find no new profiles. |
| stored_profiles.clear(); |
| EXPECT_FALSE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| ASSERT_TRUE(stored_profiles.empty()); |
| } |
| |
| TEST_F(ProfileProviderTest, SuspendDone_NoUserLoggedIn_NoCollection) { |
| // No user is logged in, so no collection is done on resume from suspend. |
| profile_provider_->SuspendDone(base::Minutes(10)); |
| // Run all pending tasks. |
| task_environment_.FastForwardBy(kMaxCollectionDelay); |
| |
| std::vector<SampledProfile> stored_profiles; |
| EXPECT_FALSE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| EXPECT_TRUE(stored_profiles.empty()); |
| } |
| |
| TEST_F(ProfileProviderTest, CanceledSuspend_NoCollection) { |
| // Set user state as logged in. This activates periodic collection, but we can |
| // deactivate it for each collector. |
| ash::LoginState::Get()->SetLoggedInState( |
| ash::LoginState::LOGGED_IN_ACTIVE, |
| ash::LoginState::LOGGED_IN_USER_REGULAR); |
| for (auto& collector : profile_provider_->collectors_) { |
| collector->Deactivate(); |
| } |
| |
| // Trigger a canceled suspend (zero sleep duration). |
| profile_provider_->SuspendDone(base::Seconds(0)); |
| // Run all pending tasks. |
| task_environment_.FastForwardBy(kMaxCollectionDelay); |
| |
| // We should find no profiles. |
| std::vector<SampledProfile> stored_profiles; |
| EXPECT_FALSE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| ASSERT_TRUE(stored_profiles.empty()); |
| } |
| |
| TEST_F(ProfileProviderTest, SuspendDone) { |
| // Set user state as logged in. This activates periodic collection, but other |
| // triggers like SUSPEND_DONE take precedence. |
| ash::LoginState::Get()->SetLoggedInState( |
| ash::LoginState::LOGGED_IN_ACTIVE, |
| ash::LoginState::LOGGED_IN_USER_REGULAR); |
| |
| // Trigger a resume from suspend. |
| profile_provider_->SuspendDone(base::Minutes(10)); |
| // Run all pending tasks. |
| task_environment_.FastForwardBy(kMaxCollectionDelay); |
| |
| // We should find two profiles, one for each collector. |
| std::vector<SampledProfile> stored_profiles; |
| EXPECT_TRUE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| ExpectTwoStoredPerfProfiles( |
| stored_profiles, SampledProfile::RESUME_FROM_SUSPEND, |
| THERMAL_STATE_NOMINAL, base::PowerThermalObserver::kSpeedLimitMax); |
| } |
| |
| TEST_F(ProfileProviderTest, OnSessionRestoreDone_NoUserLoggedIn_NoCollection) { |
| // No user is logged in, so no collection is done on session restore. |
| profile_provider_->OnSessionRestoreDone(nullptr, 10); |
| // Run all pending tasks. |
| task_environment_.FastForwardBy(kMaxCollectionDelay); |
| |
| std::vector<SampledProfile> stored_profiles; |
| EXPECT_FALSE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| EXPECT_TRUE(stored_profiles.empty()); |
| } |
| |
| TEST_F(ProfileProviderTest, OnSessionRestoreDone) { |
| // Set user state as logged in. This activates periodic collection, but we can |
| // deactivate it for each collector. |
| ash::LoginState::Get()->SetLoggedInState( |
| ash::LoginState::LOGGED_IN_ACTIVE, |
| ash::LoginState::LOGGED_IN_USER_REGULAR); |
| for (auto& collector : profile_provider_->collectors_) { |
| collector->Deactivate(); |
| } |
| |
| // Trigger a session restore. |
| profile_provider_->OnSessionRestoreDone(nullptr, 10); |
| // Run all pending tasks. |
| task_environment_.FastForwardBy(kMaxCollectionDelay); |
| |
| // We should find two profiles, one for each collector. |
| std::vector<SampledProfile> stored_profiles; |
| EXPECT_TRUE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| ExpectTwoStoredPerfProfiles(stored_profiles, SampledProfile::RESTORE_SESSION, |
| THERMAL_STATE_NOMINAL, |
| base::PowerThermalObserver::kSpeedLimitMax); |
| } |
| |
| TEST_F(ProfileProviderTest, ThermalStateChangesAreCaptured) { |
| // Simulate a user log in, which should activate periodic collection for all |
| // collectors. |
| ash::LoginState::Get()->SetLoggedInState( |
| ash::LoginState::LOGGED_IN_ACTIVE, |
| ash::LoginState::LOGGED_IN_USER_REGULAR); |
| test_power_monitor_source_.GenerateThermalThrottlingEvent( |
| base::PowerThermalObserver::DeviceThermalState::kCritical); |
| |
| // Run all pending tasks. SetLoggedInState has activated timers for periodic |
| // collection causing timer based pending tasks. |
| task_environment_.FastForwardBy(kPeriodicCollectionInterval); |
| // We should find two profiles, one for each collector. |
| std::vector<SampledProfile> stored_profiles; |
| EXPECT_TRUE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| ExpectTwoStoredPerfProfiles( |
| stored_profiles, SampledProfile::PERIODIC_COLLECTION, |
| THERMAL_STATE_CRITICAL, base::PowerThermalObserver::kSpeedLimitMax); |
| } |
| |
| TEST_F(ProfileProviderTest, CpuSpeedChangesAreCaptured) { |
| // Simulate a user log in, which should activate periodic collection for all |
| // collectors. |
| ash::LoginState::Get()->SetLoggedInState( |
| ash::LoginState::LOGGED_IN_ACTIVE, |
| ash::LoginState::LOGGED_IN_USER_REGULAR); |
| test_power_monitor_source_.GenerateSpeedLimitEvent(50); |
| |
| // Run all pending tasks. SetLoggedInState has activated timers for periodic |
| // collection causing timer based pending tasks. |
| task_environment_.FastForwardBy(kPeriodicCollectionInterval); |
| // We should find two profiles, one for each collector. |
| std::vector<SampledProfile> stored_profiles; |
| EXPECT_TRUE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| ExpectTwoStoredPerfProfiles(stored_profiles, |
| SampledProfile::PERIODIC_COLLECTION, |
| THERMAL_STATE_NOMINAL, 50); |
| } |
| |
| // Test profile collection triggered when a jank starts. |
| TEST_F(ProfileProviderTest, JankMonitorCallbacks) { |
| // Jankiness collection requires that the user is logged in. |
| ash::LoginState::Get()->SetLoggedInState( |
| ash::LoginState::LOGGED_IN_ACTIVE, |
| ash::LoginState::LOGGED_IN_USER_REGULAR); |
| |
| // Trigger a jankiness collection. |
| profile_provider_->OnJankStarted(); |
| task_environment_.RunUntilIdle(); |
| |
| // We should find two profiles, one for each collector. |
| std::vector<SampledProfile> stored_profiles; |
| EXPECT_TRUE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| |
| EXPECT_EQ(2U, stored_profiles.size()); |
| ExpectTwoStoredPerfProfiles(stored_profiles, SampledProfile::JANKY_TASK, |
| THERMAL_STATE_NOMINAL, |
| base::PowerThermalObserver::kSpeedLimitMax); |
| } |
| |
| // Test throttling of JANKY_TASK collections: no consecutive collections within |
| // jankiness_collection_min_interval(). |
| TEST_F(ProfileProviderTest, JankinessCollectionThrottled) { |
| // Jankiness collection requires that the user is logged in. |
| ash::LoginState::Get()->SetLoggedInState( |
| ash::LoginState::LOGGED_IN_ACTIVE, |
| ash::LoginState::LOGGED_IN_USER_REGULAR); |
| |
| // The first JANKY_TASK collection should succeed. |
| profile_provider_->OnJankStarted(); |
| task_environment_.RunUntilIdle(); |
| |
| std::vector<SampledProfile> stored_profiles; |
| |
| EXPECT_TRUE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| EXPECT_EQ(2U, stored_profiles.size()); |
| ExpectTwoStoredPerfProfiles(stored_profiles, SampledProfile::JANKY_TASK, |
| THERMAL_STATE_NOMINAL, |
| base::PowerThermalObserver::kSpeedLimitMax); |
| |
| stored_profiles.clear(); |
| |
| // We are about to fast forward the clock a lot. Deactivate all collectors |
| // to disable periodic collections. |
| for (auto& collector : profile_provider_->collectors_) { |
| collector->Deactivate(); |
| } |
| |
| // Fast forward time to 1 second before the throttling duration is over. |
| task_environment_.FastForwardBy( |
| profile_provider_->jankiness_collection_min_interval() - |
| base::Seconds(1)); |
| |
| // This collection within the minimum interval should be throttled. |
| profile_provider_->OnJankStarted(); |
| task_environment_.RunUntilIdle(); |
| |
| EXPECT_FALSE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| stored_profiles.clear(); |
| |
| // Move the clock forward past the throttling duration. The next JANKY_TASK |
| // collection should succeed. |
| task_environment_.FastForwardBy(base::Seconds(1)); |
| |
| profile_provider_->OnJankStarted(); |
| task_environment_.RunUntilIdle(); |
| |
| EXPECT_TRUE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| EXPECT_EQ(2U, stored_profiles.size()); |
| ExpectTwoStoredPerfProfiles(stored_profiles, SampledProfile::JANKY_TASK, |
| THERMAL_STATE_NOMINAL, |
| base::PowerThermalObserver::kSpeedLimitMax); |
| } |
| |
| // This class enables the jank monitor to test collections triggered by jank |
| // callbacks from the jank monitor. |
| class ProfileProviderJankinessTest : public ProfileProviderTest { |
| public: |
| void SetUp() override { |
| ProfileProviderTest::SetUp(); |
| // Jankiness collection requires that the user is logged in. |
| ash::LoginState::Get()->SetLoggedInState( |
| ash::LoginState::LOGGED_IN_ACTIVE, |
| ash::LoginState::LOGGED_IN_USER_REGULAR); |
| // Deactivate each collectors to disable periodic collections. |
| for (auto& collector : profile_provider_->collectors_) { |
| collector->Deactivate(); |
| } |
| } |
| }; |
| |
| // Test profile collection triggered by a UI thread jank. |
| TEST_F(ProfileProviderJankinessTest, JankMonitor_UI) { |
| EXPECT_TRUE(profile_provider_->jank_monitor()); |
| // Post a janky task to the UI thread. |
| content::GetUIThreadTaskRunner({})->PostTask( |
| FROM_HERE, base::BindLambdaForTesting([&]() { |
| // This is a janky task that runs for 2 seconds. |
| task_environment_.FastForwardBy(base::Seconds(2)); |
| })); |
| task_environment_.RunUntilIdle(); |
| |
| std::vector<SampledProfile> stored_profiles; |
| EXPECT_TRUE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| |
| EXPECT_EQ(2U, stored_profiles.size()); |
| ExpectTwoStoredPerfProfiles(stored_profiles, SampledProfile::JANKY_TASK, |
| THERMAL_STATE_NOMINAL, |
| base::PowerThermalObserver::kSpeedLimitMax); |
| } |
| |
| // Test profile collection triggered by an IO thread jank. |
| TEST_F(ProfileProviderJankinessTest, JankMonitor_IO) { |
| EXPECT_TRUE(profile_provider_->jank_monitor()); |
| // Post a janky task to the IO thread. |
| content::GetIOThreadTaskRunner({})->PostTask( |
| FROM_HERE, base::BindLambdaForTesting([&]() { |
| // This is a janky task that runs for 2 seconds. |
| task_environment_.FastForwardBy(base::Seconds(2)); |
| })); |
| task_environment_.RunUntilIdle(); |
| |
| std::vector<SampledProfile> stored_profiles; |
| EXPECT_TRUE(profile_provider_->GetSampledProfiles(&stored_profiles)); |
| |
| EXPECT_EQ(2U, stored_profiles.size()); |
| ExpectTwoStoredPerfProfiles(stored_profiles, SampledProfile::JANKY_TASK, |
| THERMAL_STATE_NOMINAL, |
| base::PowerThermalObserver::kSpeedLimitMax); |
| } |
| |
| namespace { |
| |
| class TestStockProfileProvider : public ProfileProvider { |
| public: |
| TestStockProfileProvider() = default; |
| |
| using ProfileProvider::collectors_; |
| |
| TestStockProfileProvider(const TestStockProfileProvider&) = delete; |
| TestStockProfileProvider& operator=(const TestStockProfileProvider&) = delete; |
| }; |
| |
| } // namespace |
| |
| class ProfileProviderStockTest : public testing::Test { |
| public: |
| ProfileProviderStockTest() = default; |
| |
| ProfileProviderStockTest(const ProfileProviderStockTest&) = delete; |
| ProfileProviderStockTest& operator=(const ProfileProviderStockTest&) = delete; |
| |
| void SetUp() override { |
| // ProfileProvider requires ash::LoginState and |
| // chromeos::PowerManagerClient to be initialized. |
| chromeos::PowerManagerClient::InitializeFake(); |
| ash::LoginState::Initialize(); |
| } |
| |
| void TearDown() override { |
| ash::LoginState::Shutdown(); |
| chromeos::PowerManagerClient::Shutdown(); |
| } |
| |
| protected: |
| content::BrowserTaskEnvironment task_environment_; |
| }; |
| |
| TEST_F(ProfileProviderStockTest, CheckSetup) { |
| TestStockProfileProvider profile_provider; |
| // We should have one collector registered. |
| EXPECT_EQ(1u, profile_provider.collectors_.size()); |
| |
| // After initialization, we should still have a single collector. |
| profile_provider.Init(); |
| EXPECT_EQ(1u, profile_provider.collectors_.size()); |
| } |
| |
| } // namespace metrics |