[Beowulf] Slection from processor choices; Requesting Giudence

[laytonjb at charter.net]

---- Geoff Jacobs <gdjacobs at gmail.com> wrote: 
> laytonjb at charter.net wrote:
> <snip>
> > - The network/MPI combination is fairly critical to good performance and to
> > price/performance. I have done some benchmarks where the right MPI library
> > on GigE produces faster results than a bad MPI library on Myrinet. Seems
> > counter-intuitive, but I've seen it.
> > - The MPI is pretty important to good performance particularly on GigE. One
> > benchmark I did showed over a 2X in performance on LAM compared to
> > MPICH1. I know MPICH1 is really old and we have a shiny new MPICH2, but
> > you would be suprised how many people start with MPICH1 and how many
> > people stick with it.
> Do you have some anecdotal numbers for different MPI libraries over GigE?

Sure. This is for one specific CFD code. Let's assum that MPICH 1 is the basline.
MPICH2 was twice as fast (half the run time). LAM was 30% faster than MPICH2.
Scali MPI Connect was 20% faster than LAM. Altogether, Scali MPI Connect
was twice as fast as MPICH1.

Is this what you were looking for?

Jeff