I have a server running CentOS 6 with Plesk 12 and basically it's pretty new but for some reason it's sometimes pretty slow and takes several seconds to respond. Most of my sites are using Wordpress and quite often I get an error 500 when I upgrade simple plugins through the WP Dashboard.
When I check the server load of my server it's often higher than 0.6 and sometimes goes up to 1.7. CPU Load for apache requests is pretty high. Single requests eat up 50-70% CPU for several seconds. Don't know if this normal as I have no clue about server administration!
Is this something you could take and look at and fix?
I look forward to hearing from you.