I was developing an app using the excellent Chrome WebView remote debugging (enabled using the following code in the app)

        if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT)
            WebView.setWebContentsDebuggingEnabled(true);

and noticed that when testing against the live server suddenly what should have been a 100ms request was taking 2-5 seconds to return. I looked at the server and thought the load was a bit high so started up more server processes but that didn’t do anything to solve the problem. Finally, when I closed down the inspector window everything went back to normal. I guess the inspector window (network monitor panel at least) was blocking the process waiting for all the data to be transferred over usb. Annoying but an easy fix to close the inspector window.