Okay, I did some better testing and here are the method, followed by results.

My data has 337 rows and 3 columns. For every test I reload the page and perform the same action – which is to open the column chooser and hide one column (always the same). To measure performance I used Firebug's console.profile/End() around the $('option',select).each loop in the “apply_perm” function of columnChooser.

I did the test five times for each of the five versions of the code and averaged the times. First version is original. Second is with Oleg's original fix – $(this.cells).css(“display”, show);. Third one is with further simplfication via this.cells.style.display = show;. Fourth is with each loops replaced with for loops in the showHideCol function. Fifth and final one is where I replace the $('option',select).each part with a for loop.

1. 24173 calls, average time 451.4ms
2. 4453 calls, average time 311.4ms
3. 1393 calls, average time 283.4ms
4. 1045 calls, average time 279ms
5. 1026 calls, average time 277.2ms

Total (from 1 to 5) reduction in number of calls made is almost 24 times, and timing improved by almost 40%. Obviously the biggest improvement was going from 1 to 2, however, considering the triviality of further optimizations I see no reason not to implement all of them.

So the code inside showHideCol, i.e. this

$("tr",$t.grid.hDiv).each(function(){


Hi guys,

This fix can be further optimized using this

$(this.cells)[0].style.display = show;

It doesn't really improve performance (at least not in any noticeable fashion) but it does reduce the number of calls made (since $.css() does a whole bunch of stuff).