[Beowulf] More cores/More processors/More nodes?

Mattijs Janssens m.janssens at opencfd.co.uk
Fri Sep 29 02:48:09 PDT 2006

You would use one thread per core (or even less) and use e.g. MPI to do the 
communication. Any MPI transfer between cores on the same processor will 
probably automatically be done using shared memory or some memory mapping 
operation. Coding this explicitly (your 'mixed-mode' model) would gain you 
nothing or very little.


> They would need to be ported to use MPI on a cluster.  However, I do not
> understand
> what happens when you have multi-processor/multi-core nodes in a
> cluster.  Do you
> just use MPI (with each thread using its own non-shared memory) or is
> there any
> way to do "mixed-mode" programming which takes advantage of shared
> memory within a
> node (like, an MPI/OpenMP hybrid?).
> Peter Wainwright


Mattijs Janssens

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