Bug 1139513 - Warn and gather data if ServiceWorker hits max workers …

…per domain limit. r=bent, r=rvitillo
dothq · Mar 25, 2015 · 60663a3 · 60663a3
1 parent 987f6f9
commit 60663a3
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diff --git a/dom/locales/en-US/chrome/dom/dom.properties b/dom/locales/en-US/chrome/dom/dom.properties
@@ -161,3 +161,5 @@ XMLDocumentLoadPrincipalMismatch=Use of document.load forbidden on Documents tha
 IndexedDBTransactionAbortNavigation=An IndexedDB transaction that was not yet complete has been aborted due to page navigation.
 # LOCALIZATION NOTE (WillChangeBudgetWarning): Do not translate Will-change, %1$S,%2$S,%3$S are numbers.
 WillChangeBudgetWarning=Will-change memory consumption is too high. Surface area covers %1$S pixels, budget is the document surface area multiplied by %2$S (%3$S pixels). All occurences of will-change in the document are ignored when over budget.
+# LOCALIZATION NOTE: Do not translate "ServiceWorker".
+HittingMaxWorkersPerDomain=A ServiceWorker could not be started immediately because other documents in the same origin are already using the maximum number of workers. The ServiceWorker is now queued and will be started after some of the other workers have completed.
diff --git a/dom/workers/RuntimeService.cpp b/dom/workers/RuntimeService.cpp
@@ -14,6 +14,7 @@
 #include "nsIObserverService.h"
 #include "nsIPrincipal.h"
 #include "nsIScriptContext.h"
+#include "nsIScriptError.h"
 #include "nsIScriptSecurityManager.h"
 #include "nsISupportsPriority.h"
 #include "nsITimer.h"
@@ -26,6 +27,7 @@
 #include "jsfriendapi.h"
 #include "mozilla/ArrayUtils.h"
 #include "mozilla/CycleCollectedJSRuntime.h"
+#include "mozilla/Telemetry.h"
 #include "mozilla/TimeStamp.h"
 #include "mozilla/dom/asmjscache/AsmJSCache.h"
 #include "mozilla/dom/AtomList.h"
@@ -1414,6 +1416,12 @@ RuntimeService::RegisterWorker(JSContext* aCx, WorkerPrivate* aWorkerPrivate)
 
   nsCString sharedWorkerScriptSpec;
 
+  const bool isServiceWorker = aWorkerPrivate->IsServiceWorker();
+  if (isServiceWorker) {
+    AssertIsOnMainThread();
+    Telemetry::Accumulate(Telemetry::SERVICE_WORKER_SPAWN_ATTEMPTS, 1);
+  }
+
   bool isSharedOrServiceWorker = aWorkerPrivate->IsSharedWorker() ||
                                  aWorkerPrivate->IsServiceWorker();
   if (isSharedOrServiceWorker) {
@@ -1461,6 +1469,19 @@ RuntimeService::RegisterWorker(JSContext* aCx, WorkerPrivate* aWorkerPrivate)
 
     if (queued) {
       domainInfo->mQueuedWorkers.AppendElement(aWorkerPrivate);
+      if (isServiceWorker) {
+        AssertIsOnMainThread();
+        // ServiceWorker spawn gets queued due to hitting max workers per domain
+        // limit so let's log a warning.
+        // Note: aWorkerPrivate->GetDocument() call might result nullptr due to
+        // no window so the message warning will show up in the browser console.
+        nsContentUtils::ReportToConsole(nsIScriptError::warningFlag,
+                                        NS_LITERAL_CSTRING("DOM"),
+                                        aWorkerPrivate->GetDocument(),
+                                        nsContentUtils::eDOM_PROPERTIES,
+                                        "HittingMaxWorkersPerDomain");
+        Telemetry::Accumulate(Telemetry::SERVICE_WORKER_SPAWN_GETS_QUEUED, 1);
+      }
     }
     else if (parent) {
       domainInfo->mChildWorkerCount++;
@@ -1529,6 +1550,10 @@ RuntimeService::RegisterWorker(JSContext* aCx, WorkerPrivate* aWorkerPrivate)
     return false;
   }
 
+  if (isServiceWorker) {
+    AssertIsOnMainThread();
+    Telemetry::Accumulate(Telemetry::SERVICE_WORKER_WAS_SPAWNED, 1);
+  }
   return true;
 }
 

diff --git a/toolkit/components/telemetry/Histograms.json b/toolkit/components/telemetry/Histograms.json
@@ -7697,5 +7697,20 @@
     "expires_in_version": "never",
     "kind": "count",
     "description": "Count plugin hang notices in e10s"
+  },
+  "SERVICE_WORKER_SPAWN_ATTEMPTS": {
+    "expires_in_version": "50",
+    "kind": "count",
+    "description": "Count attempts to spawn a ServiceWorker for a domain"
+  },
+  "SERVICE_WORKER_WAS_SPAWNED": {
+    "expires_in_version": "50",
+    "kind": "count",
+    "description": "Count ServiceWorkers that really did get a thread created for them"
+  },
+  "SERVICE_WORKER_SPAWN_GETS_QUEUED": {
+    "expires_in_version": "50",
+    "kind": "count",
+    "description": "Tracking whether a ServiceWorker spawn gets queued due to hitting max workers per domain limit"
   }
 }