(j3.2006) (SC22WG5.3668) [ukfortran] N1755: Request for new features from MPI Forum
Wed Nov 12 15:47:01 EST 2008
On Nov 11 2008, Aleksandar Donev wrote:
>> This one is very simple, anyway. As far as the program is concerned, MPI
>> transfers are semantically just a specialised form of I/O. Does anyone
>> seriously dispute that?
> I am not, obviously I proposed to extend the already existing mechanisms
> we have for async Fortran I/O to cover user-defined data transfers.
Upon thinking it over, I think that it's even simpler than I thought. And
I am even more firmly of the view that the right attribute is ASYNCHRONOUS
and not VOLATILE - the latter is toxic in all languages that have it.
All that really needs saying (in Fortran) is that a companion processor can
set and clear the pending attribute and create an ID in a processor
dependent fashion. MPI then needs to say that it does precisely that - MPI
is a perfectly respectable companion processor, after all! If an
implementor can't get it right after that, he or she is beyond redemption.
Now, tying that up in standardsese is not not easy :-(
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