[Beowulf] Really efficient MPIs??

[f.costen at cs.man.ac.uk]

Dear Jeff

> If you are going to use GigE (TCP), I would recommend Scali MPI
> (www.scali.com). It's commercial, but it's the best MPI I've ever tested
> (the fastest). Plus it works with TCP, Myrinet, and IB without having
> to recompile.
> 
> If you don't want to pay money for an MPI, then go with Open-MPI.
So Open-MPI is different from OpenMP, isn't it ?
as OpenMP is only for the shared memory architecture.
I did various tests for the hybrid case( OpenMP and MPI )
for my FDTD(finite difference time domain) calculation and
when I use supercomputers[particularly Bull](using 8 nodes and
8 cores in one node), calculation with MPI for all the
communication
is faster than OpenMP.
Best wishes, Fumie