Bug 658305 - Use journal_size_limit on places.sqlite.

r=dietrich

toolkit/components/places/Helpers.cpp

@@ -355,9 +355,10 @@ IsValidGUID(const nsCString& aGUID)
 void
 ForceWALCheckpoint(mozIStorageConnection* aDBConn)
 {
+  // Use a FULL checkpoint to ensure the operation is not dismissed by writers.
   nsCOMPtr<mozIStorageAsyncStatement> stmt;
   (void)aDBConn->CreateAsyncStatement(NS_LITERAL_CSTRING(
-    "pragma wal_checkpoint "
+    "pragma wal_checkpoint(FULL)"
   ), getter_AddRefs(stmt));
   nsCOMPtr<mozIStoragePendingStatement> handle;
   (void)stmt->ExecuteAsync(nsnull, getter_AddRefs(handle));

toolkit/components/places/nsNavHistory.cpp

@@ -810,7 +810,17 @@ nsNavHistory::InitDB()
     NS_ENSURE_SUCCESS(rv, rv);
   }
 
-  // Grow places in 10MiB increments
+  // The journal is usually free to grow for performance reasons, but it never
+  // shrinks back.  Since the space taken may be problematic, especially on
+  // mobile devices, limit its size.
+  // Since exceeding the limit will cause a truncate, allow a slightly
+  // larger limit than DATABASE_MAX_WAL_SIZE_IN_KIBIBYTES to reduce the number
+  // of times it is needed.
+  nsCAutoString journalSizePragma("PRAGMA journal_size_limit = ");
+  journalSizePragma.AppendInt(DATABASE_MAX_WAL_SIZE_IN_KIBIBYTES * 3);
+  (void)mDBConn->ExecuteSimpleSQL(journalSizePragma);
+
+  // Grow places in 10MiB increments to limit fragmentation on disk.
   (void)mDBConn->SetGrowthIncrement(10 * BYTES_PER_MEBIBYTE, EmptyCString());
 
   // We use our functions during migration, so initialize them now.