[scheduler] Enable wake-up based throttling by default

Enable wake-up based throttling by default with 3ms wake-up window. R=alexclarke@chromium.org BUG=699541 Change-Id: I9c8c273e43f812e1b296368cd227813c795d4d8d Reviewed-on: https://chromium-review.googlesource.com/1070142 Commit-Queue: Alexander Timin <altimin@chromium.org> Reviewed-by: Alex Clarke <alexclarke@chromium.org> Cr-Commit-Position: refs/heads/master@{#561535}
Denger-Network · May 24, 2018 · f456c79 · f456c79
1 parent 7c29671
commit f456c79
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Showing 5 changed files with 32 additions and 20 deletions.
diff --git a/third_party/WebKit/LayoutTests/fast/dom/resources/timer-throttling-frame.html b/third_party/WebKit/LayoutTests/fast/dom/resources/timer-throttling-frame.html
@@ -1,14 +1,17 @@
 <!DOCTYPE html>
 
-<!-- Measures the delay between two successive zero-delay timeouts. -->
+<!-- Measures the delay between two successive short-delay timeouts. 
+  Note that scheduler allows a small number of quick tasks to run without
+  throttling, so the delay is 20ms to avoid this.
+-->
 <script>
 addEventListener('message', (e) => {
   setTimeout(() => {
     let start = performance.now();
     setTimeout(() => {
       let end = performance.now();
       e.source.postMessage(end - start, e.origin);
-    }, 0);
+    }, 20);
   }, 0);
 });
 </script>
diff --git a/...arty/blink/renderer/platform/scheduler/common/throttling/task_queue_throttler_unittest.cc b/...arty/blink/renderer/platform/scheduler/common/throttling/task_queue_throttler_unittest.cc
@@ -96,6 +96,8 @@ class TaskQueueThrottlerTest : public testing::Test {
         base::sequence_manager::TaskQueueManagerForTest::Create(
             nullptr, mock_task_runner_, clock_.get()),
         base::nullopt));
+    scheduler_->GetWakeUpBudgetPoolForTesting()->SetWakeUpDuration(
+        base::TimeDelta());
     task_queue_throttler_ = scheduler_->task_queue_throttler();
     timer_queue_ = scheduler_->NewTimerTaskQueue(
         MainThreadTaskQueue::QueueType::kFrameThrottleable, nullptr);

diff --git a/third_party/blink/renderer/platform/scheduler/main_thread/main_thread_scheduler_impl.cc b/third_party/blink/renderer/platform/scheduler/main_thread/main_thread_scheduler_impl.cc
@@ -68,7 +68,8 @@ const double kSamplingRateForTaskUkm = 0.0001;
 const char kWakeUpThrottlingTrial[] = "RendererSchedulerWakeUpThrottling";
 const char kWakeUpDurationParam[] = "wake_up_duration_ms";
 
-constexpr base::TimeDelta kDefaultWakeUpDuration = base::TimeDelta();
+constexpr base::TimeDelta kDefaultWakeUpDuration =
+    base::TimeDelta::FromMilliseconds(3);
 
 base::TimeDelta GetWakeUpDuration() {
   int duration_ms;
@@ -1829,6 +1830,7 @@ IdleTimeEstimator* MainThreadSchedulerImpl::GetIdleTimeEstimatorForTesting() {
 }
 
 WakeUpBudgetPool* MainThreadSchedulerImpl::GetWakeUpBudgetPoolForTesting() {
+  InitWakeUpBudgetPoolIfNeeded();
   return main_thread_only().wake_up_budget_pool;
 }
 
@@ -2704,17 +2706,22 @@ MainThreadSchedulerImpl::GetVirtualTimeDomain() {
 
 void MainThreadSchedulerImpl::AddQueueToWakeUpBudgetPool(
     MainThreadTaskQueue* queue) {
-  if (!main_thread_only().wake_up_budget_pool) {
-    main_thread_only().wake_up_budget_pool =
-        task_queue_throttler()->CreateWakeUpBudgetPool("renderer_wake_up_pool");
-    main_thread_only().wake_up_budget_pool->SetWakeUpRate(1);
-    main_thread_only().wake_up_budget_pool->SetWakeUpDuration(
-        GetWakeUpDuration());
-  }
+  InitWakeUpBudgetPoolIfNeeded();
   main_thread_only().wake_up_budget_pool->AddQueue(tick_clock()->NowTicks(),
                                                    queue);
 }
 
+void MainThreadSchedulerImpl::InitWakeUpBudgetPoolIfNeeded() {
+  if (main_thread_only().wake_up_budget_pool)
+    return;
+
+  main_thread_only().wake_up_budget_pool =
+      task_queue_throttler()->CreateWakeUpBudgetPool("renderer_wake_up_pool");
+  main_thread_only().wake_up_budget_pool->SetWakeUpRate(1);
+  main_thread_only().wake_up_budget_pool->SetWakeUpDuration(
+      GetWakeUpDuration());
+}
+
 TimeDomain* MainThreadSchedulerImpl::GetActiveTimeDomain() {
   if (main_thread_only().use_virtual_time) {
     return GetVirtualTimeDomain();

diff --git a/third_party/blink/renderer/platform/scheduler/main_thread/main_thread_scheduler_impl.h b/third_party/blink/renderer/platform/scheduler/main_thread/main_thread_scheduler_impl.h
@@ -653,6 +653,8 @@ class PLATFORM_EXPORT MainThreadSchedulerImpl
                          PageSchedulerImpl* page_scheduler,
                          size_t page_schedulers_to_attribute);
 
+  void InitWakeUpBudgetPoolIfNeeded();
+
   // Indicates that scheduler has been shutdown.
   // It should be accessed only on the main thread, but couldn't be a member
   // of MainThreadOnly struct because last might be destructed before we

diff --git a/third_party/blink/renderer/platform/scheduler/main_thread/page_scheduler_impl_unittest.cc b/third_party/blink/renderer/platform/scheduler/main_thread/page_scheduler_impl_unittest.cc
@@ -168,8 +168,8 @@ TEST_F(PageSchedulerImplTest, RepeatingTimer_PageInBackgroundThenForeground) {
   ThrottleableTaskQueue()->PostDelayedTask(
       FROM_HERE,
       MakeRepeatingTask(ThrottleableTaskQueue(), &run_count,
-                        base::TimeDelta::FromMilliseconds(1)),
-      base::TimeDelta::FromMilliseconds(1));
+                        base::TimeDelta::FromMilliseconds(20)),
+      base::TimeDelta::FromMilliseconds(20));
 
   mock_task_runner_->RunForPeriod(base::TimeDelta::FromSeconds(1));
   EXPECT_EQ(1, run_count);
@@ -180,9 +180,7 @@ TEST_F(PageSchedulerImplTest, RepeatingTimer_PageInBackgroundThenForeground) {
 
   run_count = 0;
   mock_task_runner_->RunForPeriod(base::TimeDelta::FromSeconds(1));
-  EXPECT_EQ(1001, run_count);  // Note we end up running 1001 here because the
-  // task was posted while throttled with a delay of 1ms so the first task was
-  // due to run before the 1s period started.
+  EXPECT_EQ(50, run_count);
 }
 
 TEST_F(PageSchedulerImplTest, RepeatingLoadingTask_PageInBackground) {
@@ -214,18 +212,18 @@ TEST_F(PageSchedulerImplTest, RepeatingTimers_OneBackgroundOneForeground) {
   ThrottleableTaskQueue()->PostDelayedTask(
       FROM_HERE,
       MakeRepeatingTask(ThrottleableTaskQueue(), &run_count1,
-                        base::TimeDelta::FromMilliseconds(1)),
-      base::TimeDelta::FromMilliseconds(1));
+                        base::TimeDelta::FromMilliseconds(20)),
+      base::TimeDelta::FromMilliseconds(20));
   ThrottleableTaskQueueForScheduler(frame_scheduler2.get())
       ->PostDelayedTask(
           FROM_HERE,
           MakeRepeatingTask(
               ThrottleableTaskQueueForScheduler(frame_scheduler2.get()),
-              &run_count2, base::TimeDelta::FromMilliseconds(1)),
-          base::TimeDelta::FromMilliseconds(1));
+              &run_count2, base::TimeDelta::FromMilliseconds(20)),
+          base::TimeDelta::FromMilliseconds(20));
 
   mock_task_runner_->RunForPeriod(base::TimeDelta::FromSeconds(1));
-  EXPECT_EQ(1000, run_count1);
+  EXPECT_EQ(50, run_count1);
   EXPECT_EQ(1, run_count2);
 }