加速Web服务以自动完成并避免过多的方法调用

So I've got my jquery autocomplete 'working,' but its a little fidgety since I call the webservice method each time a keydown() fires so I get lots of methods hanging and sometimes to get the "auto" to work I have to type it out and backspace a bit because i'm assuming it got its return value a little slow. I've limited the query results to 8 to mininmize time. Is there anything i can do to make this a little snappier? This thing seems near useless if I don't get it a little more responsive.So I've got my jquery autocomplete 'working,' b