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From: Brian Barrett (brbarret_at_[hidden])
Date: 2006-08-30 10:38:57


Correct. With the exception of MPI_BOOL / MPI_LOGICAL, we do not handle
sending datatypes that are different sizes on the sender and receiver.
So sending an MPI_LONG from a 32 bit machine to a 64 bit machine will
not work correctly.

Brian

On Wed, 2006-08-30 at 10:33 -0400, Jeff Squyres wrote:
> Oops! My mistake -- thanks for the correction...
>
> I am still correct in thinking that we do not properly handle *size*
> endianness, right? Meaning that if sizeof(long) on one node is different
> than sizeof(long) on another, running an MPI job across those two nodes will
> cause Bad Things to occur if you try to exchange MPI_LONGs between the MPI
> processes, right? (and similar for other datatypes that are different
> sizes)
>
>
> On 8/30/06 9:38 AM, "Brian Barrett" <brbarret_at_[hidden]> wrote:
>
> > Actually, Jeff is incorrect. As of Open MPI 1.1, we do support endian
> > conversion between peers. It has not been as well tested as the rest of
> > the code base, but it should work. Please let us know if you have any
> > issues with that mode and we'll work to resolve them.
> >
> > Brian
> >
> >
> > On Wed, 2006-08-30 at 06:36 -0400, Jeff Squyres wrote:
> >> Open MPI does not yet support endian conversion between peers in a single
> >> MPI job. It's on the to-do list, but it's been a lower priority than some
> >> other features and issues.
> >>
> >>
> >>
> >> On 8/30/06 4:12 AM, "Eng. A.A. Isola" <alfonso.isola_at_[hidden]> wrote:
> >>
> >>> Hi everybody,
> >>>
> >>> I got one doudt in OPEN-MPI. Suppose, if
> >>> i
> >>> run the application on different systems with different data formats
> >>> (little-endian & big endian)...Willl OPEN-MPI converts from little
> >>> endian
> >>> to big-endian(if it is sending data from for eg, Linux Pc &
> >>> Solaris)....
> >>>
> >>> If it isn't able to do this, it will be able in the
> >>> future releases? (is in your to do list?)
> >>>
> >>> Thanking u for ur response,
> >>>
> >>> A.A. Isola
> >>>
> >>> _______________________________________________
> >>> users mailing list
> >>> users_at_[hidden]
> >>> http://www.open-mpi.org/mailman/listinfo.cgi/users
> >>
> >
> >
> > _______________________________________________
> > users mailing list
> > users_at_[hidden]
> > http://www.open-mpi.org/mailman/listinfo.cgi/users
>
>