ZFS on a single disk?

[Ollivier Robert]

According to Dr Josef Karthauser:
> I guess I should have been a bit clearer, I mean without any external devices backing them. Seeing as this is to be running on a VPS/Xen at a hosting environment I'm not able to add any additional devices. 

It will work even w/o anything added.  I've run an amd64 VM for several months like that.

> I'm not memory starved however. Is it madness to use a memory disk? (The instance in question will have 6gb of ram total to play with.).

You could use an md device to serve as a cache but with only 6 GB, just let ZFS use whatever it needs.
-- 
Ollivier ROBERT -=- FreeBSD: The Power to Serve! -=- roberto at keltia.net
In memoriam to Ondine, our 2nd child: http://ondine.keltia.net/