[Mpi-forum] MPI One-Sided Communication

[Vinod tipparaju]

Don't forget matching. The model depends on a relation between send and receive. This is the fundamental reason for potential difference in overlap. If you talk implementation, which we technically shouldn't for this argument, eventually the fact that a matching receiver is required for a send does impact over multiple sends.  

the one-sided model
a->b 
is independent of b. 
the two sided model
a<->b
because of its dependance implies validity -- you can hide the cost of validity but can't eliminate it.  
Vinod.
> From: keith.d.underwood at intel.com
> To: mpi-forum at lists.mpi-forum.org
> Date: Mon, 27 Apr 2009 06:48:57 -0600
> Subject: Re: [Mpi-forum] MPI One-Sided Communication
> 
> 
>>On the Earth Simulator, there are/were several application codes which are
>>using one-sided communication (instead of 2-sided). They used one-sided
>>communication especially to overlap communication and computation.
>>When I remember correctly, at least one of this applications won a Gordon
>>Bell Award of SC.
> 
> The ambiguity of the progress rule notwithstanding, there is no particular reason that one-sided should give you better overlap than two-sided.  If this is the reason that people use one-sided, maybe we should revisit the progress rule ;-)
> 
> Keith
> 
> _______________________________________________
> mpi-forum mailing list
> mpi-forum at lists.mpi-forum.org
> http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi-forum
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mpi-forum.org/pipermail/mpi-forum/attachments/20090427/6fa33f20/attachment-0001.html>