[Experiment] purge-and-suspend

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 1721 matching lines @@
   } else {
     renderer_scheduler_->OnRendererForegrounded();
     is_renderer_suspended_ = false;
   }
 }
 
 void RenderThreadImpl::OnProcessPurgeAndSuspend() {
   ChildThreadImpl::OnProcessPurgeAndSuspend();
   if (is_renderer_suspended_)
     return;
-  // TODO(hajimehoshi): Implement purging e.g. cache (crbug/607077)
+
+  base::MemoryPressureListener::NotifyMemoryPressure(
+      base::MemoryPressureListener::MEMORY_PRESSURE_LEVEL_CRITICAL);
+  base::allocator::ReleaseFreeMemory();
+
   is_renderer_suspended_ = true;
   renderer_scheduler_->SuspendRenderer();
 }
 
 void RenderThreadImpl::OnCreateNewFrame(FrameMsg_NewFrame_Params params) {
   CompositorDependencies* compositor_deps = this;
   RenderFrameImpl::CreateFrame(
       params.routing_id, params.proxy_routing_id, params.opener_routing_id,
       params.parent_routing_id, params.previous_sibling_routing_id,
       params.replication_state, compositor_deps, params.widget_params,
@@ skipping 488 matching lines @@
       v8_memory_pressure_level == v8::MemoryPressureLevel::kCritical)
     v8_memory_pressure_level = v8::MemoryPressureLevel::kModerate;
 
   blink::mainThreadIsolate()->MemoryPressureNotification(
       v8_memory_pressure_level);
   blink::MemoryPressureNotificationToWorkerThreadIsolates(
       v8_memory_pressure_level);
 }
 
 }  // namespace content