I'm not looking to move virtual machines between physical platforms; just want some protection between applications sharing a physical server. They'll all be using local disk in one form or another.
Much the easiest to manage is just having the virtual machine use a file in dom0 as its disk. Without pre-allocating, this lets me over-commit somewhat to cover unknown future needs, for example.
The alternative seems to be LVM partitions. Those are easy to throw around too, but after enough creation / destruction you can end up with your free-space fragmented so you can't use it, right?
But I imagine there's a performance benefit to LVM partitions over dom0 files.
For things like foswiki for internal use by a development team, and Nagios monitoring for about a dozen systems, do i need that extra performance?
Does anybody have a rule-of-thumb for the difference?