         if (parameters.count > 0) {
             serializeRequestParameters()
         }
+        
+        if _requestOperationQueue == nil {
+            _requestOperationQueue = NSOperationQueue()
+            _requestOperationQueue!.maxConcurrentOperationCount = 4
+            _requestOperationQueue!.name = "com.yayuhh.YYHRequest"
+        }
 
         connection = NSURLConnection(request: request(), delegate: self)
-        connection!.setDelegateQueue(operationQueue)
+        connection!.setDelegateQueue(_requestOperationQueue)
         connection!.start()
     }
     


import Foundation

let operationQueue = NSOperationQueue()

class YYHRequest: NSObject, NSURLConnectionDataDelegate {
    typealias YYHRequestCompletionHandler = (NSURLResponse?, NSData?, NSError?) -> Void

    init(url: NSURL) {
        self.url = url
        completionHandler = {response, data, error in}
    }
    
    // Request Loading
