jQuery ajax request cancelled slows the current request
Remember too that opening an AJAX request to the server, and then canceling the request will not cancel the request from processing on the server, it simply stops the browser from listening for a response. The server will continue to process any disconnected ajax requests until they finish running, at which point it tries to send a response to the client and finding no one listening, dies.
jQuery('#my_input').focusout(function(){ jQuery.xhrPool.abortAll();}); blur event in that it supports detecting the loss of focus from parent elements