[Beowulf] Alternative to MPI ABI

[Greg Lindahl]

On Fri, Mar 25, 2005 at 02:59:18PM -0500, Patrick Geoffray wrote:

> I don't see it that way. First, the implementations of the translation 
> layers will be done by each MPI implementations.

In which case it's basically the same as doing an ABI. Or did I miss
something?  Does this somehow save a significant amount of work for
anyone?

> >Was there a big fight over the Fortran interface? It nails down the
> >types because it has to. All the ABI does is make C look like Fortran;
> >no internals need change in any implementation.
> 
> You don't change internals, you translate them. Let say you use pointers 
> in your MPI implementation and the common layer specifies integers. In 
> your translation layer, you translate pointers into integers by putting 
> them in a table. You have as much work as your internals are far from 
> the common interface and, hopefully, it will be a midpoint for everybody.

Patrick, if you read what both Jeff and I wrote, I believe it's clear
we both understand that part, because we've both mentioned that
particular implementation solution. What I was trying to understand
was why Jeff thought this was a huge nightmare.

-- greg