My server sometimes has huge loads that I think are generated by apache, but I can't explain why, it started 2 days ago to be more noticeable but from time to time I already had the server stalling It can go to a server load of 1.xx to 90.xx, and then back again. I am running a forum (vbulletin) on this machine, nothing else, on busy hours I have up to 2000 users online, but server stalls sometimes even in non-busy hours. Also apache is generating huge logs and I don't seem to be able to prevent that (using ISPConfig). What kind of optimisations can i do to apache and mysql to make it run smoothly? Should I upgrade apache and mysql? I only upgrade by doing yum update, but that is not upgrading my mysql and apache to the latest versions.
Please check your Apache error log. Also, this guide might be of interest: http://www.howtoforge.com/configuring_apache_for_maximum_performance
