Open MPI logo

Open MPI User's Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Open MPI User's mailing list

Subject: Re: [OMPI users] MPI_Allreduce on local machine
From: David Zhang (solarbikedz_at_[hidden])
Date: 2010-07-27 12:06:06


Try mpi_real8 for the type in allreduce

On 7/26/10, Hugo Gagnon <sourceforge.openmpi_at_[hidden]> wrote:
> Hello,
>
> When I compile and run this code snippet:
>
> 1 program test
> 2
> 3 use mpi
> 4
> 5 implicit none
> 6
> 7 integer :: ierr, nproc, myrank
> 8 integer, parameter :: dp = kind(1.d0)
> 9 real(kind=dp) :: inside(5), outside(5)
> 10
> 11 call mpi_init(ierr)
> 12 call mpi_comm_size(mpi_comm_world, nproc, ierr)
> 13 call mpi_comm_rank(mpi_comm_world, myrank, ierr)
> 14
> 15 inside = (/ 1, 2, 3, 4, 5 /)
> 16 call mpi_allreduce(inside, outside, 5, mpi_double_precision,
> mpi_sum, mpi_comm_world, ierr)
> 17
> 18 print*, myrank, inside
> 19 print*, outside
> 20
> 21 call mpi_finalize(ierr)
> 22
> 23 end program test
>
> I get the following error, with say 2 processors:
>
> forrtl: severe (174): SIGSEGV, segmentation fault occurred
> Image PC Routine Line
> Source
> libmpi.0.dylib 00000001001BB4B7 Unknown Unknown
> Unknown
> libmpi_f77.0.dyli 00000001000AF046 Unknown Unknown
> Unknown
> a.out 0000000100000CE2 _MAIN__ 16
> test.f90
> a.out 0000000100000BDC Unknown Unknown
> Unknown
> a.out 0000000100000B74 Unknown Unknown
> Unknown
> forrtl: severe (174): SIGSEGV, segmentation fault occurred
> Image PC Routine Line
> Source
> libmpi.0.dylib 00000001001BB4B7 Unknown Unknown
> Unknown
> libmpi_f77.0.dyli 00000001000AF046 Unknown Unknown
> Unknown
> a.out 0000000100000CE2 _MAIN__ 16
> test.f90
> a.out 0000000100000BDC Unknown Unknown
> Unknown
> a.out 0000000100000B74 Unknown Unknown
> Unknown
>
> on my iMac having compiled OpenMPI with ifort according to:
> http://software.intel.com/en-us/articles/performance-tools-for-software-developers-building-open-mpi-with-the-intel-compilers/
>
> Note that the above code snippet runs fine on my school parallel cluster
> where ifort+intelmpi is installed.
> Is there something special about OpenMPI's MPI_Allreduce function call
> that I should be aware of?
>
> Thanks,
> --
> Hugo Gagnon
>
> _______________________________________________
> users mailing list
> users_at_[hidden]
> http://www.open-mpi.org/mailman/listinfo.cgi/users
>

-- 
Sent from my mobile device
David Zhang
University of California, San Diego