[Beowulf] clustering using xen virtualized machines

[Jon Forrest]

At a recent Rocks clustering user's group
meeting the recent addition of Rocks support of
Xen-based virtual clusters came up. Some
of the same questions recently raised on this
list were discussed there.

One justification for virtual clusters that I
hadn't thought of was discussed. This only applies
in places with large clusters run by a central
computing group but used by various internal
customers. Using virtual clusters makes it
very easy to supply clusters to customers
who need a cluster for a limited period of
time. The amount of effort necessary to
provision a new cluster is minimal.
Nodes can easily and quickly be added,
if necessary. This is as opposed to buying
a new cluster for a research group, using it
for a couple of months, and then turning it
off.

So, in this case, virtualized clusters have
the advantage of being easier to manage. The
performance overhead caused by the virtualization
is a factor, but it's decreasing as time goes
on due to better hardware support of virtualization
and cleverer software.

Cordially,
-- 
Jon Forrest
Research Computing Support
College of Chemistry
173 Tan Hall
University of California Berkeley
Berkeley, CA
94720-1460
510-643-1032
jlforrest at berkeley.edu