I noticed wordpress is hogging 50% to 100% of my dedicated server's CPU on a single request so I started to do some testing.
(Watch in 1080p or you can't see anything)
Debian6, 2GB RAM, 2x 1.6GHz
So I made a copy of the website and put it on a VPS with Debian5, 512MB RAM, shared 4x 2.5GHz . I disabled all wordpress plug-ins prior to this test.
It's using *way* too much. 10 simultaneous connections causes 100% load on all 4 cores.
So, it happens on both servers, so it's obviously something wordpress related. Plugins are off so it can't be that. So I tried installing xcache, it didn't help ;(
I use lighttpd as a webserver, btw. I read some people's posts over the internets saying they get ~50.000 pageviews per day and don't even come near to the resources I am using up with 10 requests.
What can be causing this?