Reland "Throttle resource message requests during user interaction"

content/renderer/render_thread_impl.cc

Index: content/renderer/render_thread_impl.cc
diff --git a/content/renderer/render_thread_impl.cc b/content/renderer/render_thread_impl.cc
index 87f14c3d941598cbde5140d396d4f52a65d20d52..182d95837808d8033334b26d72ed2a832e484e71 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -104,6 +104,7 @@
 #include "content/renderer/render_view_impl.h"
 #include "content/renderer/renderer_blink_platform_impl.h"
 #include "content/renderer/scheduler/renderer_scheduler.h"
+#include "content/renderer/scheduler/throttled_message_sender.h"
 #include "content/renderer/service_worker/embedded_worker_context_message_filter.h"
 #include "content/renderer/service_worker/embedded_worker_dispatcher.h"
 #include "content/renderer/shared_worker/embedded_shared_worker_stub.h"
@@ -195,6 +196,8 @@ namespace {
 const int64 kInitialIdleHandlerDelayMs = 1000;
 const int64 kLongIdleHandlerDelayMs = 30*1000;
 
+const int kMaxResourceMessageRequestsPerSecondWhenThrottled = 60 * 4;

[picksi1, 2015/01/13 11:24:44]

Can you add a comment to explain how you got to this value?

[jdduke (slow), 2015/01/13 16:18:11]

Yup, done.

+
 // Maximum allocation size allowed for image scaling filters that
 // require pre-scaling. Skia will fallback to a filter that doesn't
 // require pre-scaling if the default filter would require an
@@ -469,6 +472,10 @@ void RenderThreadImpl::Init() {
       thread_safe_sender()));
   renderer_scheduler_ = RendererScheduler::Create();
   channel()->SetListenerTaskRunner(renderer_scheduler_->DefaultTaskRunner());
+  throttled_resource_sender_.reset(new ThrottledMessageSender(
+      static_cast<RenderThread*>(this), renderer_scheduler_.get(),
+      kMaxResourceMessageRequestsPerSecondWhenThrottled));
+  resource_dispatcher()->set_message_sender(throttled_resource_sender_.get());
   embedded_worker_dispatcher_.reset(new EmbeddedWorkerDispatcher());
 
   media_stream_center_ = NULL;