Re: [netcdfgroup] OpenMPI MPI_COMM_WORLD

• To: netcdfgroup@xxxxxxxxxxxxxxxx
• Subject: Re: [netcdfgroup] OpenMPI MPI_COMM_WORLD
• From: David Robertson <robertson@xxxxxxxxxxxxxxxxxx>
• Date: Tue, 27 Jan 2009 12:37:49 -0500

 >> Hi,
 >>
>> I am having a problem with OpenMPI and NetCDF4 Fortran 90 parallel IO.
>> I'm fairly certain the problem is with NetCDF and not HDF5 because 'make
>> check' for HDF5 tests the C AND Fortran 90 parallel IO and all tests
>> pass. I have traced this problem extensively in TotalView and it seems
>> to stem from the fact that MPI_COMM_WORLD is zero in the Fortran 90
>> interface for OpenMPI. In contrast, MPICH2 Fortran 90 interface sets
>> MPI_COMM_WORLD to 1140850688.
>
> David,
>
> How are you specifying MPI_COMM_WORLD? Are you defining your own
> constant?
>
> In my case I find a fortran header file called mpif.h, which I include
> in my fortran program to get a definition for MPI_COMM_WORLD...
 >
 > Ed

Ed,

I am not defining my own constant, I'm using the MPI_COMM_WORLD
parameter from OpenMPI's mpif.h. That's how MPI_COMM_WORLD gets set to 0
instead of 1140850688. I have been interacting with the OpenMPI group
and they have said that MPI_COMM_WORLD for the Fortran interface is
"hard-wired" to be zero.

Is there a reason the Fortran 90 interface for NetCDF-4 is not using
HDF5's Fortran 90 interface?

Dave

• Follow-Ups:
  • Re: [netcdfgroup] OpenMPI MPI_COMM_WORLD
    • From: Ed Hartnett

• References:
  • [netcdfgroup] OpenMPI MPI_COMM_WORLD
    • From: David Robertson