Slow columns filtering on larga data set

wariat

Hi,
I'm using approach described in https://datatables.net/examples/api/multi_filter.html to filter on individual columns in datatables with >7000 rows. And column search works more slowly then filtering using global search box. Here is example http://jsfiddle.net/4mwq4/4/ . As you can see there is some miliseconds gap while typing but when I type in global search box - filter is applied instantly. Do I need to apply additional configuration to make it work quicker?

Please advise,