[Mpi3-rma] request-based ops

[Jeff Hammond]

So Wes was telling me about IWIN_FLUSH yesterday (this function is a
great idea, btw) and the alternative of adding double-request RPUT and
RACCUMULATE that provide a request for both local and remote
completion.  By induction, this would imply a triple-request
RGET_ACCUMULATE operation, which I also think is a good idea.  It's
really silly to have to wait for the result buffer to be ready to
reuse the origin buffer in RGET_ACCUMULATE.  It seems that many
implementations will be able to send the entire origin buffer a
nontrivial amount of time before the result comes back, particularly
if the remote side doesn't have hardware-based progress and the data
has to wait in a network buffer.

I'm sorry that I missed the last day of the Forum in San Jose.  I
didn't know these operations were on the table.  They sound like a
great idea to me.

Jeff

-- 
Jeff Hammond
Argonne Leadership Computing Facility
University of Chicago Computation Institute
jhammond at alcf.anl.gov / (630) 252-5381
http://www.linkedin.com/in/jeffhammond
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