More than 3 seconds "Initial Connection" time (webpagetest.org)

Posted by George Tasioulis on Server Fault See other posts from Server Fault or by George Tasioulis
Published on 2012-09-24T01:41:57Z Indexed on 2012/09/24 3:40 UTC
Read the original article Hit count: 496

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linux

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webserver

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litespeed

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ttfb

I'm having a weird issue with a vBulletin forum, on a 2? Xeon E5645 w/ 16GB RAM, cPanel and LiteSpeed webserver; It takes too long to start loading...

When I tested it with webpagetest.org I saw that for every request there's a 3 second "Initial connection" delay, which I don't know why is happening. Here's a screenshot: enter image description here

CPU Load is between 0.03 and 0.05, I've got several GB of free RAM, practical no I/O activity, and this delay can occur even with only one visitor on the forum.

Where do you suggest I start searching? What could be the reason for this kind of delay? I don't think it's the webserver, or the forum because there's another website on the server (total 2 sites) which is WordPress based, and has exactly the same issue with the 3 second initial connection delay. I believe it's OS related, but need a clue on where to start looking.

Thanks in advance :)

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