Request takes ages

Hi,

First of all, I’ve read many articles and other forum entries but i cant seem to get an hold on it.

Background:
I have a VPS with directadmin (my own webhosting) and around 10 sites on it now. Some dynamic (read wordpress) en some just static html. Nothing big.

Just added a new (development) site on the server and sometimes the request just won’t load while other do. I don’t see any CPU/RAM spikes, disk usages is normal and it isn’t outgoing traffic.

The unfortunate thing is that it works most of the time, but sometimes just stops for periods of 10 minutes and it won’t load, while other sites continue to function…

I disabled the The7 theme and all plugins and couldn’t detect a difference. I set out to create my own theme but also with my own theme (nothing fancy and all codex example code for now) it still has that problem.

What is an (easy) way to debug this more? Afaik it’s only THIS site and other aren’t affected….

Thanks,

Sem