[mpich-discuss] Need some help on basic issues

[Dr. C. B. Basak]

Dear MPICH users,

I have been using MPICH for almost last 2 years and now I think I have
to upgrade my system. Before doing that I had some basic questions in
my mind (I do not know much about computer hardware) and I would
appreciate your help very much in this regards.

Info:

I run simulation program that is processor intensive rather than data intensive.

Questions:

1. 4 CPUs in same motherboard vs. 4 x (1 CPU in 1 motherboard)
connected via switch/ infiband etc. which one would be faster for
processing intensive application?

2. If there are 2 no. of six core processors; then what does "fully
parallel processing" mean? 2 parallel processes (2 processors) or 12
parallel processes (12 cores)? (if there are 2 threads for each core,
then does that mean 24 parallel processes?). What I mean is that what
would be optimum no. of parallel process (-n ) for such configuration.

3. In parallel processing should the hyper-threading be on or off?

Eagerly waiting for replies.

Best Regards,

C. B. Basak