Slow request handling

apache, performance, php

[guruyaya]

Some system data before I start: Apache/2.2.3, Php v5.2.0 installed from source code using CentOs 4.3.

I run several sites using ip based virtual host. My pages went a bit slow from time to time, so I've created a test that send a request to the sites and I've added a log to my php scripts that shows me when the script started working. (simply file_put_contents('mylogfile', $testid.' - started on: '.date('h-i-s')) Let me show you a small piece of this log, from one of the failed tests I had:

1375616659 - started on: 09-15-18

Now this is a part of my apache log. I'm using mod_log_firstbyte to show when the answer to the request was started to be sent to the client.

[Test machine IP address] - - [29/Jan/2007:09:15:13 -0600] "GET /?TestId=1375616659&date=09-15-13 HTTP/1.0" 200 64064 "-" "Test Bot" 6268201 6219483

(I'm using TestId to match the test with the apache record, and date to show when the client sent the request, the clocks are syncronized) As you can see, the request got to the server on 09:15:13, but php started handling it on 09-15-18. What happend then? I've first thought it's resolving issue, as my log was set with hostnamelookups on. But after the hostnamelookups went off, I had a rather small change.

Can anyone think of an idea how to resolve this problem? I'll be forever greatful

Thanks
GuruYaya