didReceiveResponse takes very long time
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In my app, i am setting NSURLConnection every time i come from background to foreground from applicationWillEnterForeground. It works fine normally (takes 1 sec for getting didReceiveResponse), but when i put my application on background for more than around 5 mins, it takes a long time for getting the response (didReceiveResponse  in 7 - 8 seconds). More is the time in background, more time it takes. What can be the reason? Thanks!