Service Worker: Add UMA for stopping workers.

These may help us understand the cause of
stalled-in-stopping workers.

BUG=509904

Review URL: https://codereview.chromium.org/1276773002

Cr-Commit-Position: refs/heads/master@{#342253}

4 files changed, 33 insertions, 0 deletions

diff --git a/content/browser/service_worker/embedded_worker_instance.cc b/content/browser/service_worker/embedded_worker_instance.cc
index c79fdfe..c2ec4a3 100644
--- a/content/browser/service_worker/embedded_worker_instance.cc
+++ b/content/browser/service_worker/embedded_worker_instance.cc
@@ -5,6 +5,7 @@
 #include "content/browser/service_worker/embedded_worker_instance.h"
 
 #include <algorithm>
+#include <string>
 #include <utility>
 
 #include "base/bind_helpers.h"
@@ -197,6 +198,8 @@ ServiceWorkerStatusCode EmbeddedWorkerInstance::Stop() {
   // the status to STOPPING.
   status_ = STOPPING;
   FOR_EACH_OBSERVER(Listener, listener_list_, OnStopping());
+  UMA_HISTOGRAM_ENUMERATION("ServiceWorker.SendStopWorker.Status", status,
+                            SERVICE_WORKER_ERROR_MAX_VALUE);
   return status;
 }
 
diff --git a/content/renderer/service_worker/embedded_worker_dispatcher.cc b/content/renderer/service_worker/embedded_worker_dispatcher.cc
index 1bd384a..8fcea3b 100644
--- a/content/renderer/service_worker/embedded_worker_dispatcher.cc
+++ b/content/renderer/service_worker/embedded_worker_dispatcher.cc
@@ -5,6 +5,7 @@
 #include "content/renderer/service_worker/embedded_worker_dispatcher.h"
 
 #include "base/memory/scoped_ptr.h"
+#include "base/metrics/histogram_macros.h"
 #include "base/strings/string16.h"
 #include "base/strings/utf_string_conversions.h"
 #include "content/child/child_process.h"
@@ -59,6 +60,13 @@ bool EmbeddedWorkerDispatcher::OnMessageReceived(
 
 void EmbeddedWorkerDispatcher::WorkerContextDestroyed(
     int embedded_worker_id) {
+  if (ContainsKey(stop_worker_times_, embedded_worker_id)) {
+    base::TimeTicks stop_time = stop_worker_times_[embedded_worker_id];
+    UMA_HISTOGRAM_MEDIUM_TIMES("ServiceWorker.TerminateThread.Time",
+                               base::TimeTicks::Now() - stop_time);
+    stop_worker_times_.erase(embedded_worker_id);
+  }
+
   RenderThreadImpl::current()->thread_safe_sender()->Send(
       new EmbeddedWorkerHostMsg_WorkerStopped(embedded_worker_id));
   workers_.Remove(embedded_worker_id);
@@ -105,6 +113,7 @@ void EmbeddedWorkerDispatcher::OnStopWorker(int embedded_worker_id) {
   // This should eventually call WorkerContextDestroyed. (We may need to post
   // a delayed task to forcibly abort the worker context if we find it
   // necessary)
+  stop_worker_times_[embedded_worker_id] = base::TimeTicks::Now();
   wrapper->worker()->terminateWorkerContext();
 }
 
diff --git a/content/renderer/service_worker/embedded_worker_dispatcher.h b/content/renderer/service_worker/embedded_worker_dispatcher.h
index c11ea37..0ecd75a 100644
--- a/content/renderer/service_worker/embedded_worker_dispatcher.h
+++ b/content/renderer/service_worker/embedded_worker_dispatcher.h
@@ -5,9 +5,12 @@
 #ifndef CONTENT_RENDERER_SERVICE_WORKER_EMBEDDED_WORKER_DISPATCHER_H_
 #define CONTENT_RENDERER_SERVICE_WORKER_EMBEDDED_WORKER_DISPATCHER_H_
 
+#include <map>
+
 #include "base/basictypes.h"
 #include "base/id_map.h"
 #include "base/memory/weak_ptr.h"
+#include "base/time/time.h"
 #include "ipc/ipc_listener.h"
 
 struct EmbeddedWorkerMsg_StartWorker_Params;
@@ -33,6 +36,7 @@ class EmbeddedWorkerDispatcher : public IPC::Listener {
   void OnStopWorker(int embedded_worker_id);
 
   IDMap<WorkerWrapper, IDMapOwnPointer> workers_;
+  std::map<int /* embedded_worker_id */, base::TimeTicks> stop_worker_times_;
   base::WeakPtrFactory<EmbeddedWorkerDispatcher> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(EmbeddedWorkerDispatcher);
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index af3ec5c..8f4649f 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -38553,6 +38553,15 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="ServiceWorker.SendStopWorker.Status"
+    enum="ServiceWorkerStatusCode">
+  <owner>falken@chromium.org</owner>
+  <summary>
+    The result of trying to send the IPC message to a renderer process telling
+    it to stop an embedded worker. Recorded in EmbeddedWorkerInstance::Stop.
+  </summary>
+</histogram>
+
 <histogram name="ServiceWorker.StartNewWorker.Status"
     enum="ServiceWorkerStatusCode">
   <owner>falken@chromium.org</owner>
@@ -38644,6 +38653,14 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="ServiceWorker.TerminateThread.Time" units="milliseconds">
+  <owner>falken@chromium.org</owner>
+  <summary>
+    The time taken in the renderer process between the main thread asking the
+    worker thread to terminate and getting ACK that it terminated.
+  </summary>
+</histogram>
+
 <histogram name="ServiceWorker.UnhandledEventRatio" units="percent">
   <owner>kinuko@chromium.org</owner>
   <obsolete>