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Subject: Re: [OMPI users] MPI_Brecv vs multiple MPI_Irecv
From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2008-08-28 07:14:07


On Aug 27, 2008, at 8:55 AM, Robert Kubrick wrote:

> However from an application point of view I see an odd result here.
> On the sender side I can use a buffered send to "queue" messages for
> delivery and decide how many messages my buffer should contain
> before the MPI_Bsend blocks if it's running out of space.
>
> On the receiving side I have no control over the number of messages
> that MPI can buffer. This is basically left to the implementation
> details as you very well described. Shouldn't the user be allowed to
> specify a memory space to buffer messages on the receiving side,
> just like on the send?

It's worth pointing out that the MPI Forum is again meeting to work on
MPI-2.1 (small bug fixes over MPI-2.0), MPI-2.1 (bigger bug fixes over
MPI 2.0/2.1) and MPI-3.0 (entirely new stuff).

If you'd like to make a proposal to the Forum (e.g., to allow the
receive side to control buffering), I encourage you to do so. The
more specific your proposal, the better. It strikes me that such a
proposal fits within the scope of MPI-3.0.

-- 
Jeff Squyres
Cisco Systems