Re: we should wait for 1sided implementations

Ron Brightwell (bright@cs.sandia.gov)
Wed, 22 May 96 10:56:57 MDT

>
>
> At the last meeting, I was the sole dissenter in a number of the
> formal votes on the one-sided communication chapter. A colleague has
> since pointed out the essence of my unease, which is that we are
> voting to standardize an interface that has not been implemented (even
> partially) and which is not closely related to common practice.
>
> I know of no implmentation of the proposed MPI interface. My
> understanding is that at this stage in MPI-1, there was an
> implementation that tracked the current spec and provided substantial
> feedback.
>

The initialization and get/put functions have existed in our MPI
implementation on top of Puma portals for the Paragon and TeraFLOPS
machine for over two months. We have several ASCI users who are
in the process of porting their shmem codes from the T3D to our
MPI-2 one sided interface, which is essentially what was proposed
in the March 4th edition of the document. Our implementation
currently ignores the target counter argument to the put functions
(which will require a handler or something at the target), so I
voted against having this functionality at the last meeting.

I have documentation that is dated December '95 for an MPI-2 one sided
communications implementation that EPCC has done for the Cray T3D also.

-Ron