Bug 459299 - nsNavHistory::SetPageTitleInternal is slow

This caches a statement that is created any time a pages title changes.  The
creation of the statement took roughly 66% of the functions execution time
according to shark.
It also removes a transaction that was not needed in this method.
r=dietrich

toolkit/components/places/src/nsNavHistory.cpp

@@ -1337,6 +1337,15 @@ nsNavHistory::InitStatements()
     getter_AddRefs(mFoldersWithAnnotationQuery));
   NS_ENSURE_SUCCESS(rv, rv);
 
+  // mDBSetPlaceTitle
+  rv = mDBConn->CreateStatement(NS_LITERAL_CSTRING(
+      "UPDATE moz_places_view "
+      "SET title = ?1 "
+      "WHERE url = ?2"),
+    getter_AddRefs(mDBSetPlaceTitle));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+
   // mDBVisitsForFrecency
   // NOTE: we are not limiting to visits with "visit_type NOT IN (0,4,7)"
   // because if we do that, mDBVisitsForFrecency would return no visits
@@ -6587,8 +6596,6 @@ nsNavHistory::SetPageTitleInternal(nsIURI* aURI, const nsAString& aTitle)
 {
   nsresult rv;
 
-  mozStorageTransaction transaction(mDBConn, PR_TRUE);
-
   // first, make sure the page exists, and fetch the old title (we need the one
   // that isn't changing to send notifications)
   nsAutoString title;
@@ -6616,32 +6623,24 @@ nsNavHistory::SetPageTitleInternal(nsIURI* aURI, const nsAString& aTitle)
   if ((aTitle.IsVoid() && title.IsVoid()) || aTitle == title)
     return NS_OK;
 
-  nsCOMPtr<mozIStorageStatement> dbModStatement;
-  title = aTitle;
-  rv = mDBConn->CreateStatement(NS_LITERAL_CSTRING(
-      "UPDATE moz_places_view SET title = ?1 WHERE url = ?2"),
-    getter_AddRefs(dbModStatement));
-  NS_ENSURE_SUCCESS(rv, rv);
-
+  mozStorageStatementScoper scoper(mDBSetPlaceTitle);
   // title
   if (aTitle.IsVoid())
-    dbModStatement->BindNullParameter(0);
+    rv = mDBSetPlaceTitle->BindNullParameter(0);
   else
-    dbModStatement->BindStringParameter(0, StringHead(aTitle, HISTORY_TITLE_LENGTH_MAX));
+    rv = mDBSetPlaceTitle->BindStringParameter(0, StringHead(aTitle, HISTORY_TITLE_LENGTH_MAX));
   NS_ENSURE_SUCCESS(rv, rv);
 
   // url
-  rv = BindStatementURI(dbModStatement, 1, aURI);
+  rv = BindStatementURI(mDBSetPlaceTitle, 1, aURI);
   NS_ENSURE_SUCCESS(rv, rv);
 
-  rv = dbModStatement->Execute();
-  NS_ENSURE_SUCCESS(rv, rv);
-  rv = transaction.Commit();
+  rv = mDBSetPlaceTitle->Execute();
   NS_ENSURE_SUCCESS(rv, rv);
 
   // observers (have to check first if it's bookmarked)
   ENUMERATE_WEAKARRAY(mObservers, nsINavHistoryObserver,
-                      OnTitleChanged(aURI, title))
+                      OnTitleChanged(aURI, aTitle))
 
   return NS_OK;
 

toolkit/components/places/src/nsNavHistory.h

@@ -409,6 +409,7 @@ class nsNavHistory : public nsSupportsWeakReference,
   nsCOMPtr<mozIStorageStatement> mDBAddNewPage; // used by InternalAddNewPage
   nsCOMPtr<mozIStorageStatement> mDBGetTags; // used by FilterResultSet
   nsCOMPtr<mozIStorageStatement> mFoldersWithAnnotationQuery;  // used by StartSearch and FilterResultSet
+  nsCOMPtr<mozIStorageStatement> mDBSetPlaceTitle; // used by SetPageTitleInternal
 
   // these are used by VisitIdToResultNode for making new result nodes from IDs
   nsCOMPtr<mozIStorageStatement> mDBVisitToURLResult; // kGetInfoIndex_* results