And how do I know how big my data buffer is? I ran MPI_TYPE_EXTENT of And how do I know how big my data buffer is? I ran MPI_TYPE_EXTENT of MPI_DOUBLE_PRECISION and the result was 8. So I changed my program to:
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=8) :: 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_real, mpi_sum, mpi_comm_world, ierr) 17 18 if (myrank == 0) then 19 print*, outside 20 end if 21 22 call mpi_finalize(ierr) 23 24 end program test but I still get a SIGSEGV fault: 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 0000000100000D87 _MAIN__ 16 test.f90 a.out 0000000100000C9C Unknown Unknown Unknown a.out 0000000100000C34 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 0000000100000D87 _MAIN__ 16 test.f90 a.out 0000000100000C9C Unknown Unknown Unknown a.out 0000000100000C34 Unknown Unknown Unknown What is wrong now? -- Hugo Gagnon On Wed, 28 Jul 2010 07:56 -0400, "Jeff Squyres" <jsquy...@cisco.com> wrote: > On Jul 27, 2010, at 4:19 PM, Gus Correa wrote: > > > Is there a simple way to check the number of bytes associated to each > > MPI basic type of OpenMPI on a specific machine (or machine+compiler)? > > > > Something that would come out easily, say, from ompi_info? > > Not via ompi_info, but the MPI function MPI_GET_EXTENT will tell you the > datatype's size. > > ----- > [4:54] svbu-mpi:~/mpi % cat extent.f90 > program main > use mpi > implicit none > integer ierr, ext > > call MPI_INIT(ierr) > call MPI_TYPE_EXTENT(MPI_DOUBLE_PRECISION, ext, ierr) > print *, 'Type extent of DOUBLE_PREC is', ext > call MPI_FINALIZE(ierr) > > end > [4:54] svbu-mpi:~/mpi % mpif90 extent.f90 -o extent -g > [4:54] svbu-mpi:~/mpi % ./extent > Type extent of DOUBLE_PREC is 8 > [4:54] svbu-mpi:~/mpi % > ----- > > -- > Jeff Squyres > jsquy...@cisco.com > For corporate legal information go to: > http://www.cisco.com/web/about/doing_business/legal/cri/ > > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users > -- Hugo Gagnon
