[mpiwg-rma] FW: [Mpi3-rma] [EXTERNAL] Re: MPI-3 UNIFIED model updates
balaji at mcs.anl.gov
Tue Aug 27 13:19:20 CDT 2013
On 08/27/2013 12:57 PM, Jeff Hammond wrote:
> The MPI standard will not define by what mechanism the SHMEM
> implementation will establish the necessary consistency. This is what I
> mean by undefined = implementation-defined. I do not think that Keith
> is proposing to enumerate all processor memory models and the
> appropriate fences required to achieve the affect of win_sync but at
> lower cost. Thus, it is the implementation - or perhaps more
> accurately, the platform on which the implementation resides - that will
> define these semantics.
Here's what I understood from Keith --
He wants a statement in the standard that says the application can do
platform-specific memory consistency to synchronize the public and
private windows in UNIFIED.
I do agree that that's a very flimsy statement and doesn't really mean
much. But I'm calling it a definition, while I think you are saying
that it's pretty much undefined.
I like leaving it totally undefined better than the above "definition".
More information about the mpiwg-rma