[Pvfs2-users] MX help

[Robert Latham]

On Thu, Mar 05, 2009 at 09:41:55AM -0500, Scott Atchley wrote:
> Generally, I would not want to limit my MPI to TCP and IO to MX  
> especially if my TCP is over gigabit Ethernet. Unless your IO can exceed 
> the link rate, there will be plenty of bandwidth left over for MPI and 
> your latency will stay much lower than TCP.

I think that's great advice. On our old GM cluster, I ran benchmarks
whose only non-io MPI calls were "wtime" and "barrier", so
MPI-over-tcp wasn't a big deal :>

> What is PAV?

It's a collection of perl scripts that let you set up scratch pvfs
volumes.  PBS gives you a bunch of nodes, then you use PAV to set up
servers on some of them and make the others clients.  

You can find it in ./test/common/pav if you're curious.

==rob

-- 
Rob Latham
Mathematics and Computer Science Division    A215 0178 EA2D B059 8CDF
Argonne National Lab, IL USA                 B29D F333 664A 4280 315B