Which OS-level services are needed to run IRIS?

Hi,

I'm having a few issues with keeping Ubuntu happy and stable, and it seems to be something at the OS level rather than within IRIS itself. My thought is to simply pare back the stuff that Ubuntu LTS runs by default, which will free up system resources (which really shouldn't be a problem, but it might help) and reduce the amount that can go wrong.

Are there any guides as to what can be safely disabled at boot time, or are required to be enabled?