[Mpi3-hybridpm] New version of the hybrid proposal

[Pavan Balaji]

Hi Doug,

On 01/01/2010 11:09 AM, Douglas Miller wrote:
> I have attached a document to the forum, which contains notes and a
> starting discussion for the additional support for parallelism I've been
> mentioning. Unless plans have changed, I expect we will discuss this on Jan
> 5.

Thanks. Would it make sense to have some rough numbers on what the
expected benefits might be in some of the cases you outlined in the
proposal?

It looks like the helper threads would be beneficial only when the
amount of local work to be done by the MPI stack (not including network
communication) is high. The collective working group has a number of
proposals on sparse collectives, etc., which might reduce this in many
cases. If we have concrete examples where this is useful (e.g., which
collective for what communication pattern), together with some rough
numbers, it'll make the case for this proposal much stronger.

 -- Pavan

-- 
Pavan Balaji
http://www.mcs.anl.gov/~balaji