Bug 686435 - Add a telemetry probe on nsAppShellService::CreateTopLevelWindow. r=taras

toolkit/components/startup/nsAppStartup.cpp

@@ -100,6 +100,9 @@ static NS_DEFINE_CID(kAppShellCID, NS_APPSHELL_CID);
 
 using namespace mozilla;
 extern PRTime gXRE_mainTimestamp;
+// The following tracks our overhead between reaching XRE_main and loading any XUL
+extern PRTime gCreateTopLevelWindowTimestamp;// Timestamp of the first call to
+                                             // nsAppShellService::CreateTopLevelWindow
 extern PRTime gFirstPaintTimestamp;
 // mfinklesessionstore-browser-state-restored might be a better choice than the one below
 static PRTime gRestoredTimestamp = 0;       // Timestamp of sessionstore-windows-restored
@@ -713,7 +716,8 @@ enum {
   INVALID_PROCESS_CREATION = 0,
   INVALID_MAIN,
   INVALID_FIRST_PAINT,
-  INVALID_SESSION_RESTORED
+  INVALID_SESSION_RESTORED,
+  INVALID_CREATE_TOP_LEVEL_WINDOW
 };
 
 NS_IMETHODIMP
@@ -763,6 +767,11 @@ nsAppStartup::GetStartupInfo()
   else
     Telemetry::Accumulate(Telemetry::STARTUP_MEASUREMENT_ERRORS, INVALID_MAIN);
 
+  if (gCreateTopLevelWindowTimestamp >= gProcessCreationTimestamp)
+    MaybeDefineProperty(cx, obj, "createTopLevelWindow", gCreateTopLevelWindowTimestamp);
+  else
+    Telemetry::Accumulate(Telemetry::STARTUP_MEASUREMENT_ERRORS, INVALID_CREATE_TOP_LEVEL_WINDOW);
+
   if (gFirstPaintTimestamp >= gXRE_mainTimestamp)
     MaybeDefineProperty(cx, obj, "firstPaint", gFirstPaintTimestamp);
   else

toolkit/components/telemetry/TelemetryHistograms.h

@@ -174,7 +174,7 @@ HISTOGRAM(MOZ_SQLITE_PLACES_WRITE_B, 1, 32768, 3, LINEAR, "SQLite write (bytes)"
 HISTOGRAM(MOZ_SQLITE_COOKIES_WRITE_B, 1, 32768, 3, LINEAR, "SQLite write (bytes)")
 HISTOGRAM(MOZ_SQLITE_URLCLASSIFIER_WRITE_B, 1, 32768, 3, LINEAR, "SQLite write (bytes)")
 HISTOGRAM(MOZ_SQLITE_OTHER_WRITE_B, 1, 32768, 3, LINEAR, "SQLite write (bytes)")
-HISTOGRAM(STARTUP_MEASUREMENT_ERRORS, 1, 3, 4, LINEAR, "Flags errors in startup calculation()")
+HISTOGRAM(STARTUP_MEASUREMENT_ERRORS, 1, 4, 5, LINEAR, "Flags errors in startup calculation()")
 HISTOGRAM(NETWORK_DISK_CACHE_OPEN, 1, 10000, 10, EXPONENTIAL, "Time spent opening disk cache (ms)")
 HISTOGRAM(NETWORK_DISK_CACHE_TRASHRENAME, 1, 10000, 10, EXPONENTIAL, "Time spent renaming bad Cache to Cache.Trash (ms)")
 HISTOGRAM(NETWORK_DISK_CACHE_DELETEDIR, 1, 10000, 10, EXPONENTIAL, "Time spent deleting disk cache (ms)")

xpfe/appshell/src/nsAppShellService.cpp

@@ -156,6 +156,8 @@ nsAppShellService::DestroyHiddenWindow()
   return NS_OK;
 }
 
+PRTime gCreateTopLevelWindowTimestamp = 0;
+
 /*
  * Create a new top level window and display the given URL within it...
  */
@@ -171,6 +173,9 @@ nsAppShellService::CreateTopLevelWindow(nsIXULWindow *aParent,
 {
   nsresult rv;
 
+  if (!gCreateTopLevelWindowTimestamp)
+    gCreateTopLevelWindowTimestamp = PR_Now();
+
   nsWebShellWindow *newWindow = nsnull;
   rv = JustCreateTopWindow(aParent, aUrl,
                            aChromeMask, aInitialWidth, aInitialHeight,