With this in mind, that dom0 should be lightweight, is there a list of optimal minimal services to run in a CentOS dom0?
I assume no need to uninstall, just a service toggle off in runlevels 3 and 5?
I believe some apps and services might be useful if a maintenance task required some utils running out of dom0 with some burden on the domUs for a while.
Regards, Ben
Running processes in dom0 that aren't for running Xen is going to destroy your domU I/O performance. The backends are just processes. If you take time away from those processes for other things, performance will suffer. You should run some load tests and see if it suits your model, though.
Running the MySQL process in dom0 isn't going to get you very much of a performance boost if your MySQL configuration is tuned properly, either.