Httpd – Apache httpd Problem

apache-2.2httpdPROXY

I am getting intermittent issues with my site. Pages often hang with huge loading times and sometimes fail to load.

The httpd error logs contain the following:

[Wed Feb 23 06:54:17 2011] [debug] proxy_util.c(1854): proxy: grabbed scoreboard slot 0 in child 5871 for worker proxy:reverse
[Wed Feb 23 06:54:17 2011] [debug] proxy_util.c(1967): proxy: initialized single connection worker 0 in child 5871 for (*)
[Wed Feb 23 06:54:24 2011] [debug] proxy_util.c(1854): proxy: grabbed scoreboard slot 0 in child 5872 for worker proxy:reverse
[Wed Feb 23 06:54:24 2011] [debug] proxy_util.c(1873): proxy: worker proxy:reverse already initialized
[Wed Feb 23 06:54:24 2011] [debug] proxy_util.c(1967): proxy: initialized single connection worker 0 in child 5872 for (*)
[Wed Feb 23 06:59:15 2011] [debug] proxy_util.c(1854): proxy: grabbed scoreboard slot 0 in child 5954 for worker proxy:reverse
[Wed Feb 23 06:59:15 2011] [debug] proxy_util.c(1873): proxy: worker proxy:reverse already initialized

The server is currently running with 800mb free memory, so it is not caused by lack of RAM.
The current number of httpd procceses is 11. This does increase as the error persists and can rise up to 25+. Also, I am running Apache/2.2.3 (CentOS).

Any suggestions would be greatly appreciated.

Many thanks,

Chris.

EDIT

Access Log: http://pastebin.com/vRSwdhuP

httpd.conf: http://pastebin.com/effKp0ih

Please also note that this error only appears when the page is refreshed.

Best Answer

There is not enough information to give any informed guess but here are a few things you can look into or try:

  • Try running ApacheBench on the server to see if the slow page loading issue can be duplicated. For example: ab -kc 10 -t 30 http://yourserver.com/somepage.php If the pages load fast on the server then the issue is network related.
  • Try loading different types of pages (images, JS, CSS, PHP, HTML, SHTML, etc...) and see which ones load fast and which don't. If static files all load fast then the issue is something related to the dynamic page setup/execution. If all files load slow it is a more likely a general server/configuration issue.
  • Do you have other Apache configuration files (check in '/etc/httpd/conf.d/' for example). Your virtual host entries reference proxy options but no ProxyPass or similar line is found. If you are proxying requests consider that the proxy source may be slow. Test it with ApacheBench to confirm.
  • Those entries from your error log are not actual errors but just debug log statements. Errors will have a [error] header string. You can also check other error/system logs for relevant messages (/var/log/messages for example).