Site slow

My site is on a shared host at Dreamhost and teaches Ruby Programming for free for people around the world. Recently, I am experiencing very slow page loads and sometimes 500 errors.

Support mentioned - "Hmm, it looks like your 'abcde' user has been running into our process watcher. That's an automated program running on all of our servers to make sure that one user doesn't take up too much of the system's resources. The best way to keep that memory usage down is to keep your software up to date with the latest versions, and also to minimize the number of plugins or extra modules that your sites are using. Also keep in mind that the memory limits are set per-user, so any websites or processes that are running for that user will count towards that memory limit. For policy reasons I can't tell you what the limit is exactly, but it is pretty liberal. We're in the business of hosting sites, not killing processes if you get what I'm saying. ;) So there's probably just a misbehaving plugin or script that's eating up the server's memory. Or if you've gotten a dramatic increase in traffic that can account for it too."

I run my site single-handedly and don't know any system admin work or Unix. What would you suggest I need to do?
All help appreciated.

Thanks.

Satish Talim
Free Online Ruby Programming Course

The home page loaded in 16 seconds for me.

I didn't really look around much, but if you click the "Validate HTML" link at the bottom of your site, it brings up a ton of errors, so going through those might be a good start.

I don't have any experience with Moodle, but the one interesting plugin I see is the one that generates the system statistics at the bottom of every page. Is that something that you just recently added to help you debug?

Use the 3DOM50 promo code for 3 extra lifetime domains and $50 off
More Dreamhost coupons here!

I know. That's something I can't change. Moodle the software, I use is the culprit.

Satish Talim
Free Online Ruby Programming Course