[Beowulf] scratch File system for small cluster

[Glen Beane]

I am considering adding a small parallel file system ~(5-10TB) my small
cluster (~32 2x dual core Opteron nodes) that is used mostly by a handful of
regular users.  Currently the only storage accessible to all nodes is home
directory space which is provided by the Lab's IT department (this is a SAN
volume connected to the head node by 2x FC links, and NFS exported to the
compute nodes). I don't have to "worry" about the IT provided SAN space -
they back it up, provide redundant hardware, etc.  The parallel file system
would be scratch space (and not backed up by IT).  We have a mix of home
grown apps doing a pretty wide range of things (some do a lot of I/O, others
don't), and things like BLAST and BLAT.

Can anyone out there provide recommendations for a good solution for fast
scratch space for a cluster of this size?

Right now I was thinking about PVFS2. How many I/O servers should I have,
and how many cores and RAM per I/O server?
Are there other recommendations for fast scratch space (it doesn't have to
be a parallel file system, something with less hardware would be nice)

--
Glen L. Beane
Software Engineer
The Jackson Laboratory
http://www.jax.org