I was afraid that was the case. Too bad, because applications (and the files they use), are getting much too big for the 32 bit limit.
T. Rosmond On Wed, 2013-05-22 at 09:37 -0700, Ralph Castain wrote: > On May 22, 2013, at 9:23 AM, Eric Chamberland > <eric.chamberl...@giref.ulaval.ca> wrote: > > > On 05/22/2013 11:33 AM, Tom Rosmond wrote: > >> Thanks for the confirmation of the MPIIO problem. Interestingly, we > >> have the same problem when using MPIIO in INTEL MPI. So something > >> fundamental seems to be wrong. > >> > > > > I think but I am not sure that it is because the MPI I/O (ROMIO) code is > > the same for all distributions... > > > > It has been written by Rob Latham. > > > > Maybe some developers could confirm this? > > Well, ROMIO was written by Argonne/MPICH (unfair to point the finger solely > at Rob) and picked up by pretty much everyone. The issue isn't a bug in > MPIIO, but rather in the MPI functional descriptions. They stipulate that the > input param be an int, which defaults to 32-bits on the described system. So > there is no way to reference anything beyond 32-bits in size. > > Afraid you'll have to do the multiple reads, or switch to a system that > defaults to 64-bit integers. > > > > > Eric > > > >> T. Rosmond > >> > >> > >> On Wed, 2013-05-22 at 11:21 -0400, Eric Chamberland wrote: > >>> I have experienced the same problem.. and worst, I have discovered a bug > >>> in MPI I/O... > >>> > >>> look here: > >>> http://trac.mpich.org/projects/mpich/ticket/1742 > >>> > >>> and here: > >>> > >>> http://www.open-mpi.org/community/lists/users/2012/10/20511.php > >>> > >>> Eric > >>> > >>> On 05/21/2013 03:18 PM, Tom Rosmond wrote: > >>>> Hello: > >>>> > >>>> A colleague and I are running an atmospheric ensemble data assimilation > >>>> system using MPIIO. We find that if for an individual > >>>> MPI_FILE_READ_AT_ALL the block of data read exceeds 2**31 elements, the > >>>> program fails. Our application is 32 bit fortran (Intel), so we > >>>> certainly can see why this might be expected. Is this the case? We > >>>> have a workaround by doing multiple reads from the file while moving the > >>>> file view, so it isn't a serious problem. > >>>> > >>>> Thanks for any advice or suggestions > >>>> > >>>> T. Rosmond > >>>> > >>>> > >>>> > >>>> _______________________________________________ > >>>> users mailing list > >>>> us...@open-mpi.org > >>>> http://www.open-mpi.org/mailman/listinfo.cgi/users > >>>> > >>> > > > > _______________________________________________ > > users mailing list > > us...@open-mpi.org > > http://www.open-mpi.org/mailman/listinfo.cgi/users > > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users
