On Fri, Mar 25, 2005 at 05:49:13PM -0500, Jeff Squyres wrote: > MorphMPI (or, as Patrick suggests, we need a cooler name -- PatrickMPI? > ;-) ) is the work of 1 grad clever student (or anyone else industrious > enough). Elapsed time: a few months.
Right. > Making even 2 MPI implementations agree on an ABI is an enormous amount > of work. Given that two major MPI implementations take opposite sides > on the pointers-vs.integers for MPI handles debate (and I suspect that > neither is willing to change), just getting them to agree on one of > them will be a major amount of work. Then changing the internals of > one of those MPIs to match the other is another enormous amount of work > (death by a million cuts). You yourself said how MPI implementers would actually implement this without needing to change any internals: Make the C interface routines do the same thing that F77 does today. Elapsed time: a few months, same as MorphMPI. No internals need to be changed. I suppose the good news is that if this is your main objection, then it's gone. > Also, as I pointed out in my original alternate proposal, with > PatrickMPI, only those who want to use an ABI will use it. Those who > do *not* want an ABI do not have to have it forced upon them. I missed where anyone was being forced to do anything. MPI implementers can support the ABI alongside their current interface or not, it's their choice. -- greg
