     
     func numberToStringThrows(number: Int) -> Future<String> {
         let promise = Promise<String>()
-        let dispatchTime = dispatch_time(DISPATCH_TIME_NOW, Int64(0.1 * Double(NSEC_PER_SEC)))
-        dispatch_after(dispatchTime, dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_LOW, 0)) {
+        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0)) {
             promise.reject(TestError.FailedToConvertNumberToString(number))
         }
         return promise.future

    
    func numberToString(number: Int) -> Future<String> {
        let promise = Promise<String>()
        let dispatchTime = dispatch_time(DISPATCH_TIME_NOW, Int64(0.1 * Double(NSEC_PER_SEC)))
        dispatch_after(dispatchTime, dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_LOW, 0)) {
            let str = String(number)
            promise.fulfill(str)
        }

    
    func generateTestInt(number: Int) -> Future<Int> {
        let promise = Promise<Int>()
        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0)) {
            promise.fulfill(number)
        }
        return promise.future
