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content / common / android / cpu_time_metrics_internal.cc [blame]
// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/common/android/cpu_time_metrics_internal.h"
#include <stdint.h>
#include <atomic>
#include <memory>
#include <utility>
#include "base/command_line.h"
#include "base/containers/flat_map.h"
#include "base/cpu.h"
#include "base/functional/callback_helpers.h"
#include "base/lazy_instance.h"
#include "base/memory/raw_ptr.h"
#include "base/metrics/histogram_functions.h"
#include "base/metrics/histogram_macros.h"
#include "base/metrics/persistent_histogram_allocator.h"
#include "base/no_destructor.h"
#include "base/notreached.h"
#include "base/process/process_metrics.h"
#include "base/run_loop.h"
#include "base/sequence_checker.h"
#include "base/strings/pattern.h"
#include "base/strings/string_util.h"
#include "base/task/current_thread.h"
#include "base/task/task_observer.h"
#include "base/task/thread_pool.h"
#include "base/threading/platform_thread.h"
#include "base/threading/thread_id_name_manager.h"
#include "base/types/expected.h"
#include "content/common/process_visibility_tracker.h"
#include "content/public/common/content_switches.h"
#include "content/public/common/process_type.h"
namespace content {
namespace internal {
namespace {
bool g_ignore_histogram_allocator_for_testing = false;
static_assert(static_cast<int>(ProcessTypeForUma::kMaxValue) ==
PROCESS_TYPE_PPAPI_BROKER,
"ProcessTypeForUma and CurrentProcessType() require updating");
ProcessTypeForUma CurrentProcessType() {
std::string process_type =
base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
switches::kProcessType);
if (process_type.empty())
return ProcessTypeForUma::kBrowser;
if (process_type == switches::kRendererProcess)
return ProcessTypeForUma::kRenderer;
if (process_type == switches::kUtilityProcess)
return ProcessTypeForUma::kUtility;
if (process_type == switches::kSandboxIPCProcess)
return ProcessTypeForUma::kSandboxHelper;
if (process_type == switches::kGpuProcess)
return ProcessTypeForUma::kGpu;
if (process_type == switches::kPpapiPluginProcess)
return ProcessTypeForUma::kPpapiPlugin;
NOTREACHED_IN_MIGRATION() << "Unexpected process type: " << process_type;
return ProcessTypeForUma::kUnknown;
}
const char* GetPerThreadHistogramNameForProcessType(ProcessTypeForUma type) {
switch (type) {
case ProcessTypeForUma::kBrowser:
return "Power.CpuTimeSecondsPerThreadType.Browser";
case ProcessTypeForUma::kRenderer:
return "Power.CpuTimeSecondsPerThreadType.Renderer";
case ProcessTypeForUma::kGpu:
return "Power.CpuTimeSecondsPerThreadType.GPU";
default:
return "Power.CpuTimeSecondsPerThreadType.Other";
}
}
const char* GetAvgCpuLoadHistogramNameForProcessType(ProcessTypeForUma type) {
switch (type) {
case ProcessTypeForUma::kBrowser:
return "Power.AvgCpuLoad.Browser";
case ProcessTypeForUma::kRenderer:
return "Power.AvgCpuLoad.Renderer";
case ProcessTypeForUma::kGpu:
return "Power.AvgCpuLoad.GPU";
default:
return "Power.AvgCpuLoad.Other";
}
}
// Keep in sync with CpuTimeMetricsThreadType in
// //tools/metrics/histograms/enums.xml.
enum class CpuTimeMetricsThreadType {
kUnattributedThread = 0,
kOtherThread,
kMainThread,
kIOThread,
kThreadPoolBackgroundWorkerThread,
kThreadPoolForegroundWorkerThread,
kThreadPoolServiceThread,
kCompositorThread,
kCompositorTileWorkerThread,
kVizCompositorThread,
kRendererUnspecifiedWorkerThread,
kRendererDedicatedWorkerThread,
kRendererSharedWorkerThread,
kRendererAnimationAndPaintWorkletThread,
kRendererServiceWorkerThread,
kRendererAudioWorkletThread,
kRendererFileThread,
kRendererDatabaseThread,
kRendererOfflineAudioRenderThread,
kRendererReverbConvolutionBackgroundThread,
kRendererHRTFDatabaseLoaderThread,
kRendererAudioEncoderThread,
kRendererVideoEncoderThread,
kMemoryInfraThread,
kSamplingProfilerThread,
kNetworkServiceThread,
kAudioThread,
kInProcessUtilityThread,
kInProcessRendererThread,
kInProcessGpuThread,
kMaxValue = kInProcessGpuThread,
};
CpuTimeMetricsThreadType GetThreadTypeFromName(const char* const thread_name) {
if (!thread_name)
return CpuTimeMetricsThreadType::kOtherThread;
if (base::MatchPattern(thread_name, "Cr*Main")) {
return CpuTimeMetricsThreadType::kMainThread;
} else if (base::MatchPattern(thread_name, "Chrome*IOThread")) {
return CpuTimeMetricsThreadType::kIOThread;
} else if (base::MatchPattern(thread_name, "ThreadPool*Foreground*")) {
return CpuTimeMetricsThreadType::kThreadPoolForegroundWorkerThread;
} else if (base::MatchPattern(thread_name, "ThreadPool*Background*")) {
return CpuTimeMetricsThreadType::kThreadPoolBackgroundWorkerThread;
} else if (base::MatchPattern(thread_name, "ThreadPoolService*")) {
return CpuTimeMetricsThreadType::kThreadPoolServiceThread;
} else if (base::MatchPattern(thread_name, "Compositor")) {
return CpuTimeMetricsThreadType::kCompositorThread;
} else if (base::MatchPattern(thread_name, "CompositorTileWorker*")) {
return CpuTimeMetricsThreadType::kCompositorTileWorkerThread;
} else if (base::MatchPattern(thread_name, "VizCompositor*")) {
return CpuTimeMetricsThreadType::kVizCompositorThread;
} else if (base::MatchPattern(thread_name, "unspecified worker*")) {
return CpuTimeMetricsThreadType::kRendererUnspecifiedWorkerThread;
} else if (base::MatchPattern(thread_name, "DedicatedWorker*")) {
return CpuTimeMetricsThreadType::kRendererDedicatedWorkerThread;
} else if (base::MatchPattern(thread_name, "SharedWorker*")) {
return CpuTimeMetricsThreadType::kRendererSharedWorkerThread;
} else if (base::MatchPattern(thread_name, "AnimationWorklet*")) {
return CpuTimeMetricsThreadType::kRendererAnimationAndPaintWorkletThread;
} else if (base::MatchPattern(thread_name, "ServiceWorker*")) {
return CpuTimeMetricsThreadType::kRendererServiceWorkerThread;
} else if (base::MatchPattern(thread_name, "AudioWorklet*")) {
return CpuTimeMetricsThreadType::kRendererAudioWorkletThread;
} else if (base::MatchPattern(thread_name, "File thread")) {
return CpuTimeMetricsThreadType::kRendererFileThread;
} else if (base::MatchPattern(thread_name, "Database thread")) {
return CpuTimeMetricsThreadType::kRendererDatabaseThread;
} else if (base::MatchPattern(thread_name, "OfflineAudioRender*")) {
return CpuTimeMetricsThreadType::kRendererOfflineAudioRenderThread;
} else if (base::MatchPattern(thread_name, "Reverb convolution*")) {
return CpuTimeMetricsThreadType::kRendererReverbConvolutionBackgroundThread;
} else if (base::MatchPattern(thread_name, "HRTF*")) {
return CpuTimeMetricsThreadType::kRendererHRTFDatabaseLoaderThread;
} else if (base::MatchPattern(thread_name, "Audio encoder*")) {
return CpuTimeMetricsThreadType::kRendererAudioEncoderThread;
} else if (base::MatchPattern(thread_name, "Video encoder*")) {
return CpuTimeMetricsThreadType::kRendererVideoEncoderThread;
} else if (base::MatchPattern(thread_name, "MemoryInfra")) {
return CpuTimeMetricsThreadType::kMemoryInfraThread;
} else if (base::MatchPattern(thread_name, "StackSamplingProfiler")) {
return CpuTimeMetricsThreadType::kSamplingProfilerThread;
} else if (base::MatchPattern(thread_name, "NetworkService")) {
return CpuTimeMetricsThreadType::kNetworkServiceThread;
} else if (base::MatchPattern(thread_name, "AudioThread")) {
return CpuTimeMetricsThreadType::kAudioThread;
} else if (base::MatchPattern(thread_name, "Chrome_InProcUtilityThread")) {
return CpuTimeMetricsThreadType::kInProcessUtilityThread;
} else if (base::MatchPattern(thread_name, "Chrome_InProcRendererThread")) {
return CpuTimeMetricsThreadType::kInProcessRendererThread;
} else if (base::MatchPattern(thread_name, "Chrome_InProcGpuThread")) {
return CpuTimeMetricsThreadType::kInProcessGpuThread;
}
// TODO(eseckler): Also break out Android's RenderThread here somehow?
return CpuTimeMetricsThreadType::kOtherThread;
}
} // namespace
// Reports per-thread CPU time breakdowns.
class ProcessCpuTimeMetrics::DetailedCpuTimeMetrics {
public:
DetailedCpuTimeMetrics(base::ProcessMetrics* process_metrics,
ProcessTypeForUma process_type)
: process_metrics_(process_metrics),
process_type_(process_type),
// DetailedCpuTimeMetrics is created on the main thread of the process
// but lives on the thread pool sequence afterwards.
main_thread_id_(base::PlatformThread::CurrentId()) {
DETACH_FROM_SEQUENCE(thread_pool_);
}
void CollectOnThreadPool() {
DCHECK_CALLED_ON_VALID_SEQUENCE(thread_pool_);
// This might overflow. We only care that it is different for each cycle.
current_cycle_++;
// Skip reporting any values into histograms until histogram persistence is
// set up. Otherwise, we would create the histograms without persistence and
// lose data at process termination (particularly in child processes).
if (!base::GlobalHistogramAllocator::Get() &&
!g_ignore_histogram_allocator_for_testing) {
return;
}
const base::expected<base::TimeDelta, base::ProcessCPUUsageError>
cumulative_cpu_time = process_metrics_->GetCumulativeCPUUsage();
base::TimeDelta process_cpu_time_delta;
if (cumulative_cpu_time.has_value()) {
process_cpu_time_delta = cumulative_cpu_time.value() - reported_cpu_time_;
reported_cpu_time_ = cumulative_cpu_time.value();
}
// Also report a breakdown by thread type.
base::TimeDelta unattributed_delta = process_cpu_time_delta;
if (process_metrics_->GetCumulativeCPUUsagePerThread(
cumulative_thread_times_)) {
for (const auto& entry : cumulative_thread_times_) {
base::PlatformThreadId tid = entry.first;
base::TimeDelta cumulative_time = entry.second;
auto it_and_inserted = thread_details_.emplace(
tid, ThreadDetails{base::TimeDelta(), current_cycle_});
ThreadDetails* thread_details = &it_and_inserted.first->second;
if (it_and_inserted.second) {
// New thread.
thread_details->type = GuessThreadType(tid);
}
thread_details->last_updated_cycle = current_cycle_;
// Skip negative or null values, might be a transient collection error.
if (cumulative_time <= base::TimeDelta())
continue;
if (cumulative_time < thread_details->reported_cpu_time) {
// PlatformThreadId was likely reused, reset the details.
thread_details->reported_cpu_time = base::TimeDelta();
thread_details->type = GuessThreadType(tid);
}
base::TimeDelta thread_delta =
cumulative_time - thread_details->reported_cpu_time;
unattributed_delta -= thread_delta;
ReportThreadCpuTimeDelta(thread_details->type, thread_delta);
thread_details->reported_cpu_time = cumulative_time;
}
// Erase tracking for threads that have disappeared, as their
// PlatformThreadId may be reused later.
for (auto it = thread_details_.begin(); it != thread_details_.end();) {
if (it->second.last_updated_cycle == current_cycle_) {
it++;
} else {
it = thread_details_.erase(it);
}
}
}
// Report the difference of the process's total CPU time and all thread's
// CPU time as unattributed time (e.g. time consumed by threads that died).
// `unattributed_delta` can be negative if GetCumulativeCPUUsagePerThread()
// reported more time than GetCumulativeCPUUsage() did, or if
// GetCumulativeCPUUsage() failed so `unattributed_delta` started at 0.
if (unattributed_delta.is_positive()) {
ReportThreadCpuTimeDelta(CpuTimeMetricsThreadType::kUnattributedThread,
unattributed_delta);
}
}
private:
struct ThreadDetails {
base::TimeDelta reported_cpu_time;
uint32_t last_updated_cycle = 0;
CpuTimeMetricsThreadType type = CpuTimeMetricsThreadType::kOtherThread;
};
void ReportThreadCpuTimeDelta(CpuTimeMetricsThreadType type,
base::TimeDelta cpu_time_delta) {
// Histogram name cannot change after being used once. That's ok since this
// only depends on the process type, which also doesn't change.
static const char* histogram_name =
GetPerThreadHistogramNameForProcessType(process_type_);
// Histograms use int internally. Make sure it doesn't overflow.
int capped_value = std::min<int64_t>(cpu_time_delta.InMicroseconds(),
std::numeric_limits<int>::max());
UMA_HISTOGRAM_SCALED_ENUMERATION(histogram_name, type, capped_value,
base::Time::kMicrosecondsPerSecond);
}
CpuTimeMetricsThreadType GuessThreadType(base::PlatformThreadId tid) {
// Match the main thread by TID, so that this also works for WebView, where
// the main thread can have an arbitrary name.
if (tid == main_thread_id_)
return CpuTimeMetricsThreadType::kMainThread;
const char* name = base::ThreadIdNameManager::GetInstance()->GetName(tid);
return GetThreadTypeFromName(name);
}
// Accessed on |task_runner_|.
SEQUENCE_CHECKER(thread_pool_);
raw_ptr<base::ProcessMetrics> process_metrics_;
ProcessTypeForUma process_type_;
uint32_t current_cycle_ = 0;
base::PlatformThreadId main_thread_id_;
base::TimeDelta reported_cpu_time_;
base::flat_map<base::PlatformThreadId, ThreadDetails> thread_details_;
// Stored as instance variable to avoid allocation churn.
base::ProcessMetrics::CPUUsagePerThread cumulative_thread_times_;
};
// static
ProcessCpuTimeMetrics* ProcessCpuTimeMetrics::GetInstance() {
static base::NoDestructor<ProcessCpuTimeMetrics> instance;
return instance.get();
}
ProcessCpuTimeMetrics::ProcessCpuTimeMetrics()
: task_runner_(base::ThreadPool::CreateSequencedTaskRunner(
{base::TaskPriority::BEST_EFFORT,
// TODO(eseckler): Consider hooking into process shutdown on
// desktop to reduce metric data loss.
base::TaskShutdownBehavior::SKIP_ON_SHUTDOWN})),
process_metrics_(base::ProcessMetrics::CreateCurrentProcessMetrics()),
process_type_(CurrentProcessType()),
detailed_metrics_(
std::make_unique<DetailedCpuTimeMetrics>(process_metrics_.get(),
process_type_)) {
DETACH_FROM_SEQUENCE(thread_pool_);
// Browser and GPU processes have a longer lifetime (don't disappear between
// navigations), and typically execute a large number of small main-thread
// tasks. For these processes, choose a higher reporting interval.
if (process_type_ == ProcessTypeForUma::kBrowser ||
process_type_ == ProcessTypeForUma::kGpu) {
reporting_interval_ = kReportAfterEveryNTasksPersistentProcess;
} else {
reporting_interval_ = kReportAfterEveryNTasksOtherProcess;
}
task_runner_->PostTask(
FROM_HERE, base::BindOnce(&ProcessCpuTimeMetrics::InitializeOnThreadPool,
base::Unretained(this)));
base::CurrentThread::Get()->AddTaskObserver(this);
}
ProcessCpuTimeMetrics::~ProcessCpuTimeMetrics() {
DCHECK_CALLED_ON_VALID_SEQUENCE(main_thread_);
// Note that this object can only be destroyed in unit tests. We clean up
// the members and observer registrations but assume that the test takes
// care of any threading issues.
base::CurrentThread::Get()->RemoveTaskObserver(this);
ProcessVisibilityTracker::GetInstance()->RemoveObserver(this);
}
void ProcessCpuTimeMetrics::InitializeOnThreadPool() {
ProcessVisibilityTracker::GetInstance()->AddObserver(this);
PerformFullCollectionOnThreadPool();
}
// base::TaskObserver implementation:
void ProcessCpuTimeMetrics::WillProcessTask(
const base::PendingTask& pending_task,
bool was_blocked_or_low_priority) {}
void ProcessCpuTimeMetrics::DidProcessTask(
const base::PendingTask& pending_task) {
DCHECK_CALLED_ON_VALID_SEQUENCE(main_thread_);
// Periodically perform a full collection that includes |detailed_metrics_| in
// addition to high-level metrics.
task_counter_++;
if (task_counter_ == reporting_interval_) {
task_runner_->PostTask(
FROM_HERE,
base::BindOnce(
&ProcessCpuTimeMetrics::PerformFullCollectionOnThreadPool,
base::Unretained(this)));
task_counter_ = 0;
}
}
// ProcessVisibilityTracker::ProcessVisibilityObserver implementation:
void ProcessCpuTimeMetrics::OnVisibilityChanged(bool visible) {
DCHECK_CALLED_ON_VALID_SEQUENCE(thread_pool_);
// Collect high-level metrics that include a visibility breakdown and
// attribute them to the old value of |is_visible_| before updating it.
CollectHighLevelMetricsOnThreadPool();
is_visible_ = visible;
}
void ProcessCpuTimeMetrics::PerformFullCollectionOnThreadPool() {
DCHECK_CALLED_ON_VALID_SEQUENCE(thread_pool_);
CollectHighLevelMetricsOnThreadPool();
detailed_metrics_->CollectOnThreadPool();
}
void ProcessCpuTimeMetrics::CollectHighLevelMetricsOnThreadPool() {
// Skip reporting any values into histograms until histogram persistence is
// set up. Otherwise, we would create the histograms without persistence and
// lose data at process termination (particularly in child processes).
if (!base::GlobalHistogramAllocator::Get() &&
!g_ignore_histogram_allocator_for_testing) {
return;
}
const base::expected<base::TimeDelta, base::ProcessCPUUsageError>
cumulative_cpu_usage = process_metrics_->GetCumulativeCPUUsage();
base::TimeDelta process_cpu_time_delta;
if (cumulative_cpu_usage.has_value()) {
process_cpu_time_delta = cumulative_cpu_usage.value() - reported_cpu_time_;
}
// Don't report anything if GetCumulativeCPUUsage() failed or the delta is 0.
if (process_cpu_time_delta.is_positive()) {
const base::TimeDelta cumulative_cpu_time = cumulative_cpu_usage.value();
UMA_HISTOGRAM_SCALED_ENUMERATION("Power.CpuTimeSecondsPerProcessType",
process_type_,
process_cpu_time_delta.InMicroseconds(),
base::Time::kMicrosecondsPerSecond);
if (is_visible_.has_value()) {
if (*is_visible_) {
UMA_HISTOGRAM_SCALED_ENUMERATION(
"Power.CpuTimeSecondsPerProcessType.Foreground", process_type_,
process_cpu_time_delta.InMicroseconds(),
base::Time::kMicrosecondsPerSecond);
} else {
UMA_HISTOGRAM_SCALED_ENUMERATION(
"Power.CpuTimeSecondsPerProcessType.Background", process_type_,
process_cpu_time_delta.InMicroseconds(),
base::Time::kMicrosecondsPerSecond);
}
} else {
UMA_HISTOGRAM_SCALED_ENUMERATION(
"Power.CpuTimeSecondsPerProcessType.Unattributed", process_type_,
process_cpu_time_delta.InMicroseconds(),
base::Time::kMicrosecondsPerSecond);
}
reported_cpu_time_ = cumulative_cpu_time;
ReportAverageCpuLoad(cumulative_cpu_time);
}
}
void ProcessCpuTimeMetrics::ReportAverageCpuLoad(
base::TimeDelta cumulative_cpu_time) {
base::TimeTicks now = base::TimeTicks::Now();
if (cpu_load_report_time_ == base::TimeTicks()) {
cpu_load_report_time_ = now;
cpu_time_on_last_load_report_ = cumulative_cpu_time;
}
base::TimeDelta time_since_report = now - cpu_load_report_time_;
if (time_since_report >= kAvgCpuLoadReportInterval) {
base::TimeDelta cpu_time_since_report =
cumulative_cpu_time - cpu_time_on_last_load_report_;
int load = 100LL * cpu_time_since_report.InMilliseconds() /
time_since_report.InMilliseconds();
static const char* histogram_name =
GetAvgCpuLoadHistogramNameForProcessType(process_type_);
// CPU load can be greater than 100% because of multiple cores.
// That's why we use UmaHistogramCounts, not UmaHistogramPercentage.
base::UmaHistogramCounts1000(histogram_name, load);
cpu_load_report_time_ = now;
cpu_time_on_last_load_report_ = cumulative_cpu_time;
}
}
void ProcessCpuTimeMetrics::PerformFullCollectionForTesting() {
DCHECK_CALLED_ON_VALID_SEQUENCE(main_thread_);
task_runner_->PostTask(
FROM_HERE,
base::BindOnce(&ProcessCpuTimeMetrics::PerformFullCollectionOnThreadPool,
base::Unretained(this)));
}
void ProcessCpuTimeMetrics::WaitForCollectionForTesting() const {
base::RunLoop run_loop;
// Post the QuitClosure to execute after any pending collection.
task_runner_->PostTask(FROM_HERE, run_loop.QuitClosure());
run_loop.Run();
}
// static
std::unique_ptr<ProcessCpuTimeMetrics>
ProcessCpuTimeMetrics::CreateForTesting() {
std::unique_ptr<ProcessCpuTimeMetrics> ptr;
// Can't use std::make_unique due to private constructor.
ptr.reset(new ProcessCpuTimeMetrics());
return ptr;
}
// static
void ProcessCpuTimeMetrics::SetIgnoreHistogramAllocatorForTesting(bool ignore) {
g_ignore_histogram_allocator_for_testing = ignore;
}
} // namespace internal
} // namespace content