Start Render Time

[pmeenan]

(06-25-2010 02:43 PM)green-watch.org Wrote:  I suppose I should read up on this thread because I am starting to become interested in the start render time.

http://www.webpagetest.org/result/100625_GFX/1/details/

It looks like for this test it starts rendering after the document complete event was sent? Any reason why it would be sent after this event?

Sincerely,
Travis Walters

My guess would be a combination of factors. Since IE lazy-draws to the screen, the testing on FIOS changes the content fast enough that it doesn't get a chance to try to draw the screen until around doc complete but then it looks like the CPU gets completely pegged and you have some javascript (or something else really intense) firing onLoad which is blocking the main UI thread from painting as well which brings it out even further.

I'd take a look with Dynatrace Ajax edition which is a great javascript profiler for IE and it will tell you what the problematic code is. Another option to hide the problem would be to further delay your onLoad code with a timeout timer but I wouldn't recommend doing that until you have fixed the code - the long execution will block the user from being able to do anything with the page as well.

I've seen it happen on a few sites so it's not a completely unique situation.