ServiceWorker: Insert TRACE_EVENT to watch a breakdown of the ServiceWorker's performance on chome:…

content/renderer/service_worker/embedded_worker_context_client.cc

Index: content/renderer/service_worker/embedded_worker_context_client.cc
diff --git a/content/renderer/service_worker/embedded_worker_context_client.cc b/content/renderer/service_worker/embedded_worker_context_client.cc
index 627a490123f49f95ddf26599208639e7a25e1ab9..0f5ba65c13839ec48cbfe6c89f5d36c9a16545ea 100644
--- a/content/renderer/service_worker/embedded_worker_context_client.cc
+++ b/content/renderer/service_worker/embedded_worker_context_client.cc
@@ -7,6 +7,7 @@
 #include <map>
 #include <string>
 
+#include "base/debug/trace_event.h"
 #include "base/lazy_instance.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/pickle.h"
@@ -99,6 +100,16 @@ EmbeddedWorkerContextClient::EmbeddedWorkerContextClient(
       sender_(ChildThread::current()->thread_safe_sender()),
       main_thread_proxy_(base::MessageLoopProxy::current()),
       weak_factory_(this) {
+  TRACE_EVENT_ASYNC_BEGIN1("ServiceWorker",
+                           "EmbeddedWorkerContextClient",
+                           this,
+                           "Info",
+                           "Major component are the load time of SW script "

[horo, 2014/09/05 11:02:32]

I think we don't need this info.

[shimazu, 2014/09/08 07:04:46]

Done.

+                           "and preparation of execution environments.");
+  TRACE_EVENT_ASYNC_STEP_INTO0("ServiceWorker",
+                               "EmbeddedWorkerContextClient",
+                               this,
+                               "PrepareWorker");
 }
 
 EmbeddedWorkerContextClient::~EmbeddedWorkerContextClient() {
@@ -176,6 +187,12 @@ void EmbeddedWorkerContextClient::workerContextStarted(
       FROM_HERE,
       base::Bind(&EmbeddedWorkerContextClient::SendWorkerStarted,
                  weak_factory_.GetWeakPtr()));
+  TRACE_EVENT_ASYNC_STEP_INTO1(
+      "ServiceWorker",
+      "EmbeddedWorkerContextClient",
+      this,
+      "ExecuteScript",
+      "Info", "Major component is the execution time of SW script.");

[horo, 2014/09/05 11:02:32]

I think we don't need this info.

[shimazu, 2014/09/08 07:04:46]

Done.

 }
 
 void EmbeddedWorkerContextClient::willDestroyWorkerContext() {
@@ -330,6 +347,9 @@ void EmbeddedWorkerContextClient::OnMessageToWorker(
 
 void EmbeddedWorkerContextClient::SendWorkerStarted() {
   DCHECK(worker_task_runner_->RunsTasksOnCurrentThread());
+  TRACE_EVENT_ASYNC_END0("ServiceWorker",
+                         "EmbeddedWorkerContextClient",

[horo, 2014/09/05 11:02:32]

EmbeddedWorkerContextClien will keep alive after this point.
So I think "StartingWorkerContext" is better.

[shimazu, 2014/09/08 07:04:46]

I think this should contain the class name for understandability and
searchability because the appearance on the chrome:tracing is "NAME:STEP"
format. But if someone add the more ASYNC trace flow, this name is conflicting.
So I changed the name to "Class::Event" format:
"EmbeddedWorkerContextClient::StartingWorkerContext" in this case.

+                         this);
   Send(new EmbeddedWorkerHostMsg_WorkerStarted(embedded_worker_id_));
 }