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Long delays with Facebook Like, Twitter, Adsense - Printable Version

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+--- Thread: Long delays with Facebook Like, Twitter, Adsense (/showthread.php?tid=1140)



Long delays with Facebook Like, Twitter, Adsense - DisgruntledGoat - 07-29-2011 09:43 PM

I use AddThis on my site which includes the Facebook Like button and Twitter button. I also run Adsense.

Every time I run the speed test, these scripts are dramatically slowing down the load time. Each of them takes at least 6 seconds, sometimes over 20!! The DNS/TTFB are fine but the "Content Download" is what's taking the time.

But I don't get anywhere close to that when I load pages myself, even on an old computer using IE, with a cleared cache. Why is there such a big delay for WebPageTest?


RE: Long delays with Facebook Like, Twitter, Adsense - pmeenan - 07-30-2011 01:31 AM

Do you have a link to some test results to share?


RE: Long delays with Facebook Like, Twitter, Adsense - DisgruntledGoat - 07-30-2011 05:37 AM

Here is one example: http://www.webpagetest.org/result/110729_ZD_16775/1/details/


RE: Long delays with Facebook Like, Twitter, Adsense - pmeenan - 08-03-2011 05:21 AM

You've got a SERIOUS CPU utilization problem with the Javascript on that page. I re-ran the test with Dynatrace to get a javascript profile trace here: http://www.webpagetest.org/result/110802_H0_ce01f4e90dba82b8528937e35144ab75/

From what I can tell, it looks like you are dynamically adding the table to the DOM through Javascript - it looks like however that is being done took a solid 13 seconds in IE8, locking up the main thread and preventing anything else from happening.


RE: Long delays with Facebook Like, Twitter, Adsense - DisgruntledGoat - 08-04-2011 06:05 AM

How do you view the profile trace? The download on that page appears to be a zip file containing some binary files.

The table is in the page source, it's not generated on the fly. But I do use DataTables to sort the table, which may slow down the page a little. But why would that make it say the Facebook like button takes 20+ seconds to download?


RE: Long delays with Facebook Like, Twitter, Adsense - pmeenan - 08-04-2011 06:12 AM

The top logo takes you to the download page for Dynatrace Ajax Edition which is a great (free) javascript profiler for IE (and Firefox).

The Facebook like button just had the unfortunate luck to be downloading when the main browser thread locked up for 20+ seconds executing javascript (single-threaded nature of browsers, they don't do ANYTHING else when executing Javascript).


RE: Long delays with Facebook Like, Twitter, Adsense - DisgruntledGoat - 08-04-2011 10:12 AM

That's weird because it *always* seems to be the Facebook button, never a file from my site... well I'll keep looking into it and see if I can improve the performance.