Just an FYI - and I may be doing something totally invalid - but I've never
used mpi_wait with in my program that uses mpi_isend. I do however use the
mpi_request_free call for each mpi_isend, and also believe that I've insured
that all communication has completed (i.e. the corresponding mpi_recv's have
completed) before deallocating the send buffers. I run this code on
everything from Linux PC clusters to 1000 processor Origin systems and
provide it to lots of people across the country, so I'd like to address this
issue in my code if there's a problem. Is there someone that can confirm
that the mpi_wait is "absolutely" necessary, or am I somehow covered by the
steps I've taken?
Thanks - Jay LeBeau
Applied Aeroscience and CFD Branch
NASA - Johnson Space Center
Houston, TX 77058
> ----------
> From: Bora Ucar[SMTP:ubora_at_[hidden]]
> Reply To: lam_at_[hidden]
> Sent: Saturday, December 08, 2001 9:57 AM
> To: lam_at_[hidden]
> Subject: Re: LAM: Isend/Irecv
>
> > > > I am using lam6.5.3 and realized that, if you use irecv or isend you
> have
> > > > to use mpi_wait* as well. Is that so?
> > >
> > > Yes.
> >
> > Just wanted to point out that this is not a LAM-specific thing, but a
> > requirment of a correct MPI application according the MPI standard.
>
> Thanks.
> If you have time could you please explain why it is required that
> we need to call MPI_Wait after MPI_Isend? Irecv case is needed from the
> programmers perspective, but as a programmer I do not need to wait for the
> completion of MPI_Isend. It is the programmers responsibility to ensure
> the re-usage of his/her programs buffers as in the some other send modes.
> I really want to know the MPI developers' rationale behind this.
>
>
>
>
> _______________________________________________
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