[ewg] Need help for Infiniband optimisation for our cluster (MTU...)

[giggzounet]

Hi,

I'm new on this list. We have in our laboratory a little cluster:
- master 8 cores
- 8 nodes with 12 cores
- DDR infiniband switch Mellanox MTS3600R

On these machines we have an oscar cluster with CentOS 5.5. We have
installed the ofed packages 1.5.1. The default config for the infiniband
is used. So infiniband is running in connected mode.

Our cluster is used to solve CFD (Computational Fluid Dynamics)
problems. And I'm trying to optimize the infiniband network and so I
have several questions:

- Is it the right mailing list to ask ? (if not...where should I post ?)

- Is there a how-to on infiniband optimisation ?

- CFD computations need a lot of bandwidth. There are a lot of data
exchange through MPI (we are using intel mpi). Has the infiniband mode
(connected or datagram) influence in this case ? What is the "best" MTU
for those computation ?


Best regards,
Guillaume