I've got a fairly ajax heavy site and I'm trying to tune the performance.

I have a function that runs between 20 & 200 times, depending on the user. I'm outputting the time the function takes to execute via console.time in firefox.

The function takes about 4-6ms to complete.

The strange thing is that on my larger test with 200 or runs through that function, it runs through the first 31, then seems to pause for almost a second before completing the last 170 or so.

However, that 'pause' doesn't show up in the console.time logs, and I'm not running any other functions, and the object that gets passed to the function looks the same as all other objects that get passed in.

The function is called like this

for (var s in thisGroup.events){
            showEvent(thisGroup.events[s])
            }

so, I don't see how or why it would suddenly pause near the beginning. but only pause once and then continue through.

The pause ALWAYS happens on the 31st time through the function. I've taken a close look at the 'thisGroup.events[s]' that it is being run through, and it looks like this for #31

 
"eventId":"5106", "sid":"68", "gid":"29", "uid":"70","type":"event", "startDate":"2010-03-22","startTime":"6:00 PM","endDate":"2010-03-22","endTime":"11:00 PM","durationLength":"5", "durationTime":"5:00", "note":"", "desc":"event"

The event immediately after the pause, #32 looks like this

"eventId":"5111", "sid":"68", "gid":"29", "uid":"71","type":"event", "startDate":"2010-03-22","startTime":"6:00 PM","endDate":"2010-03-22","endTime":"11:00 PM","durationLength":"5", "durationTime":"5:00", "note":"", "desc":"event"

another event that runs through no problem looks like this

"eventId":"5113", "sid":"68", "gid":"29", "uid":"72","type":"event", "startDate":"2010-03-22","startTime":"4:30 PM","endDate":"2010-03-22","endTime":"11:00 PM","durationLength":"6.5", "durationTime":"6:30", "note":"", "desc":"event"

From the console outputs, it doesn't appear as there is anything hanging or taking up time in the function itself, as the console.time for each event including #31,32 is 4ms.

Another strange thing here is that the total time running the for loop across the entire object is coming out as 1014ms which is right for 200 events at 4-6ms each.

Any suggestions on how to find this 'pause'? I find it very interesting that it is consistently happening between #31 & #32 only!