Almost 3.5 Seconds Time to First Byte?

[slink]

So here is the result on a wordpress installation

http://m00.biz/Yk67Wq

Something is very, very odd. My server is usually lightning quick and has a very low load. But how can I be seeing almost 3 and a half seconds of just waiting to get started? What could be wrong? Is it the test? Take a look at this - on the same server with a vbulletin forum - it's still a terrible result but it's only .8 seconds:

http://m00.biz/TtPo95

In advance, as always, thanks for the help and for this remarkable tool.

[icc97]

(06-01-2012 12:42 PM)slink Wrote:  So here is the result on a wordpress installation

http://m00.biz/Yk67Wq

Something is very, very odd. My server is usually lightning quick and has a very low load. But how can I be seeing almost 3 and a half seconds of just waiting to get started? What could be wrong? Is it the test? Take a look at this - on the same server with a vbulletin forum - it's still a terrible result but it's only .8 seconds:

http://m00.biz/TtPo95

In advance, as always, thanks for the help and for this remarkable tool.

I've run into this slow first byte on a similar site with a WordPress installation and have the same issues. I guess this is more of an issue for discussion on a WordPress forum. It certainly is a very interesting result.

[pmeenan]

If you're up to it, I'd highly recommend installing New Relic on the server. It will give you a breakdown of where the time is going (unfortunately from the outside it's a black box).

You can also try disabling all plugins to see if it gets better and then turn them on one at a time. It could be a lot of database queries but it could also be a plugin making a call to an external service somewhere that is blocking it.

[retsek]

I see you're using W3 Total Cache.

I had this same problem. I was using APC for Page Cache in the plugin. Change it to Disk or Disk Enhanced, and you'll see better times.

[slink]

Thanks for the great suggestions - unfortunately "Optimize disk enhanced page" cannot be checked. Not sure what the problem is.

Regarding the other plugins, I've tried to disable the ones I have and they are few. Hasn't made much difference. I've gotten the TTFB down to only about 400-500ms but that still is a LOT of time in total as it's 717ms with DNS lookup, etc.

Thanks for helping me troubleshoot. Will look at New Relic but this is a mystery and it shouldn't be this hard!