time metric: record elapsed time from when the backgrounded and purged renderer is foregrounded unti

content/renderer/render_thread_impl.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/render_thread_impl.h"
 
 #include <algorithm>
 #include <limits>
 #include <map>
 #include <utility>
@@ skipping 879 matching lines @@
   ChildThreadImpl::current()->SetThreadPriority(
       categorized_worker_pool_->background_worker_thread_id(),
       base::ThreadPriority::BACKGROUND);
 #endif
 
   record_purge_suspend_metric_closure_.Reset(base::Bind(
       &RenderThreadImpl::RecordPurgeAndSuspendMetrics, base::Unretained(this)));
   record_purge_suspend_growth_metric_closure_.Reset(
       base::Bind(&RenderThreadImpl::RecordPurgeAndSuspendMemoryGrowthMetrics,
                  base::Unretained(this)));
+  needs_to_record_first_active_paint_ = false;
 
   base::MemoryCoordinatorClientRegistry::GetInstance()->Register(this);
 
   // If this renderer doesn't run inside the browser process, enable
   // SequencedWorkerPool. Otherwise, it should already have been enabled.
   // TODO(fdoray): Remove this once the SequencedWorkerPool to TaskScheduler
   // redirection experiment concludes https://crbug.com/622400.
   if (!command_line.HasSwitch(switches::kSingleProcess))
     base::SequencedWorkerPool::EnableForProcess();
 }
@@ skipping 724 matching lines @@
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
 }
 
 void RenderThreadImpl::OnProcessBackgrounded(bool backgrounded) {
   ChildThreadImpl::OnProcessBackgrounded(backgrounded);
 
   if (backgrounded) {
     renderer_scheduler_->OnRendererBackgrounded();
+    needs_to_record_first_active_paint_ = false;
   } else {
     renderer_scheduler_->OnRendererForegrounded();
     // TODO(tasak): after enabling MemoryCoordinator, remove this Notify
     // and follow MemoryCoordinator's request.
     if (base::FeatureList::IsEnabled(features::kPurgeAndSuspend))
       base::MemoryCoordinatorClientRegistry::GetInstance()->Notify(
           base::MemoryState::NORMAL);
 
     record_purge_suspend_metric_closure_.Cancel();
     record_purge_suspend_metric_closure_.Reset(
@@ skipping 19 matching lines @@
     memory_coordinator_->PurgeMemory();
   }
   // Since purging is not a synchronous task (e.g. v8 GC, oilpan GC, ...),
   // we need to wait until the task is finished. So wait 15 seconds and
   // update purge+suspend UMA histogram.
   // TODO(tasak): use MemoryCoordinator's callback to report purge+suspend
   // UMA when MemoryCoordinator is available.
   GetRendererScheduler()->DefaultTaskRunner()->PostDelayedTask(
       FROM_HERE, record_purge_suspend_metric_closure_.callback(),
       base::TimeDelta::FromSeconds(15));
+  needs_to_record_first_active_paint_ = true;
 }
 
 // TODO(tasak): Replace the following GetMallocUsage() with memory-infra
 // when it is possible to run memory-infra without tracing.
 #if defined(OS_WIN)
 namespace {
 
 static size_t GetMallocUsage() {
   // Iterate through whichever heap the CRT is using.
   HANDLE crt_heap = reinterpret_cast<HANDLE>(_get_heap_handle());
@@ skipping 744 matching lines @@
   }
 }
 
 void RenderThreadImpl::OnRendererInterfaceRequest(
     mojom::RendererAssociatedRequest request) {
   DCHECK(!renderer_binding_.is_bound());
   renderer_binding_.Bind(std::move(request));
 }
 
 }  // namespace content