[Fedora-xen] AoE with Xen

[Andy Burns]

I'm considering using AoE with Xen, my setup would be vblade on one
FC7 storage server with mdraid over 6x SATA disks, and two xen hosts
with FC7 using aoe+aoetools, using eth1 on all servers to a separate
VLAN for SAN traffic, eth0 used for normal LAN traffic, all gigabit.

I'm wondering does it make more sense to slice up /dev/md1 on the
storage server with LVM and then serve multiple /dev/VGxx/LVxx block
devices with individual vblade processes using their own AoE
shelf/slot ID to individual dom0 (or direct to AoE in domU)?

Or to serve the whole /dev/md1 using a single vblade process on the
storage server and then use CLVM or GFS on each xen dom0 to slice up a
single /dev/etherd/e0.0 in a coordinated way?

My thoughts are that using a cluster filesystem would save the hassle
of starting/stopping vblade processes whenever resizing LVs and any
associated confusion of shelf/slot IDs

But I'm not sure of the overhead of cluster filesystems, does DLM only
get involved for maintenance operations on LVs, or for all I/O
activity?

Thoughts welcome from anyone using (or having attempted) either approach ...