Apache heavy load

Question

I have a standard Centos 6.2 installation, running LAMP. Build using http://www.howtoforge.com/perfect-server-centos-6.2-x86_64-with-apache2-ispconfig-3-p2 Without the ISPconfig part.

The build is on a VM in ESX4.1, 100GB HDD 40Gb RAM

Apache load is always hogging CPU, our site is Joomla based and has heavy dynamic content.

Can anyone suggest the best settings in apache to make this run better.

This is an extremely vague, yet complex question. The first thing to do is post your current configuration. — WerkkreW, Apr 23 '12 at 14:07
The configuration is in the weblink. do I need to show my apache.conf? Thanks — Dave M, Apr 23 '12 at 14:17
Yes please. Knowing that Joomla is PHP based I have a good idea of what the issue is assuming you are running mod_php but the solution is not really easy. — WerkkreW, Apr 23 '12 at 14:27

score 3 · Answer 1 · answered Apr 23 '12 at 14:31

You can use apache top to find out which pages are the most popular ones. For those particular pages you can profile them with xdebug.

I would also try to find out if the CPU load is caused by the IO or is in user space. See: dstat, iotop, vmstat.

You can use strace -T <apache_worker_PID> on the apache worker that is clogging the CPU to see in which syscalls is spending the time.

score 2 · Answer 2 · answered Apr 23 '12 at 14:20

2

Install a caching reverse-proxy like Varnish and set it up in front of Apache.

answered Apr 23 '12 at 14:20

pkhamre

1

This is a valid suggestion but not necessarily the right answer. – WerkkreW Apr 23 '12 at 14:25

2 Answers2