by the way i want show you new way to create asynch queue
example:
dispatch_queue_t aQueue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
dispatch_async(aQueue, ^{
    [self parseDataXML];
    [self loadSettings];
});
https://developer.apple.com/library/ios/documentation/General/Conceptual/ConcurrencyProgrammingGuide/Introduction/Introduction.html