We recently became a Miva hosting partner and got the thing set up without too much trouble, and even set up a (fake) store and it seems to work fine (http://www.modwest.com/demostore).

Now we sold our first account, and it's dog-slow. The customer says it worked fine on his previous host, but that it's barely usable on our system (5-30 second waits for each page load).

Viewing 'top', puts a miva.cgi process at the top of the processlist consuming 15-40% CPU, owned by his user, for the entire waiting duration.

Our setup consists of a Linux SCSI fileserver mounted by a number of load-balanced Linux webservers, all of which are running at a load of 0.5-1.0 most of the time. We're running the XFS filesystem, and a 2.4.18 kernel. Webservers are all P3 1Ghz with 512 RAM.

Other CGIs (such as Perl, PHP, & Python) are all running fine.

What are the most common causes of Miva stores running so slowly?