v8_worker_memory_reporter.h | Explore in Territory

// 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.

#ifndef THIRD_PARTY_BLINK_RENDERER_CONTROLLER_PERFORMANCE_MANAGER_V8_WORKER_MEMORY_REPORTER_H_
#define THIRD_PARTY_BLINK_RENDERER_CONTROLLER_PERFORMANCE_MANAGER_V8_WORKER_MEMORY_REPORTER_H_

#include "base/functional/callback.h"
#include "base/gtest_prod_util.h"
#include "base/memory/weak_ptr.h"
#include "base/time/time.h"
#include "third_party/blink/public/common/tokens/tokens.h"
#include "third_party/blink/renderer/controller/controller_export.h"
#include "third_party/blink/renderer/platform/weborigin/kurl.h"
#include "third_party/blink/renderer/platform/wtf/vector.h"
#include "v8/include/v8.h"

namespace base {
class SingleThreadTaskRunner;
}

namespace blink {

class WorkerThread;

// This class measures memory usage of all workers in the renderer process.
// Memory measurement is performed by posting a task on each worker thread
// and then combining the results. Unresponsive workers (workers that never
// go back to the message loop to run tasks) are skipped after a timeout.
// The entry point is `GetMemoryUsage` that internally works as follows:
// 1. Create an instance of V8WorkerMemoryReporter.
// 2. Post a memory measurement task on each worker thread using
//    WorkerThread::CallOnAllWorkerThreads. Each task has a weak reference
//    to V8WorkerMemoryReporter.
// 3. Post a timeout task on the main thread and transfer the ownership of
//    V8WorkerMemoryReporter to the task.
// 4. Each worker task starts memory measurement using V8's MeasureMemory.
// 5. Once a measurement succeeds (or fails) a task is posted on the main
//    thread that records the result.
// 6. Once results from all workers are collected, the callback is invoked.
// 7. If there is an unresponsive worker, then the timeout task will eventually
//    run and invoke the callback with partial results.
class CONTROLLER_EXPORT V8WorkerMemoryReporter { … };

}  // namespace blink
#endif  // THIRD_PARTY_BLINK_RENDERER_CONTROLLER_PERFORMANCE_MANAGER_V8_WORKER_MEMORY_REPORTER_H_
chromium/third_party/blink/renderer/controller/performance_manager/v8_worker_memory_reporter.h
