Copyright (c) 2004-2006 The Trustees of Indiana University and Indiana
University Research and Technology
Corporation. All rights reserved.
Copyright (c) 2006-2012 Cisco Systems, Inc. All rights reserved.
Copyright (c) 2007-2009 Sun Microsystems, Inc. All rights reserved.
Copyright (c) 2010 Oracle and/or its affiliates. All rights reserved.
Copyright (c) 2013 Mellanox Technologies, Inc. All rights reserved.
The files in this directory are sample MPI applications provided both
as a trivial primer to MPI as well as simple tests to ensure that your
Open MPI installation is working properly.
If you are looking for a comprehensive MPI tutorial, these samples are
not enough. Excellent MPI tutorials are available here:
Get a free account and login; you can then browse to the list of
available courses. Look for the ones with "MPI" in the title.
There are two MPI examples in this directory, each using one of six
different MPI interfaces:
- Hello world
Fortran mpif.h: hello_mpifh.f
Fortran use mpi: hello_usempi.f90
Fortran use mpi_f08: hello_usempif08.f90
C shmem.h: hello_oshmem_c.c
Fortran shmem.fh: hello_oshmemfh.f90
- Send a trivial message around in a ring
Fortran mpif.h: ring_mpifh.f
Fortran use mpi: ring_usempi.f90
Fortran use mpi_f08: ring_usempif08.f90
C shmem.h: ring_oshmem_c.c
Fortran shmem.fh: ring_oshmemfh.f90
Additionally, there's one further example application, but this one
only uses the MPI C bindings:
- Test the connectivity between all processes
The Makefile in this directory will build as many of the examples as
you have language support (e.g., if you do not have the Fortran "use
mpi" bindings compiled as part of Open MPI, the those examples will be
The Makefile assumes that the wrapper compilers mpicc, mpic++, and
mpifort are in your path.
Although the Makefile is tailored for Open MPI (e.g., it checks the
"ompi_info" command to see if you have support for C++, mpif.h, use
mpi, and use mpi_f08 F90), all of the example programs are pure MPI,
and therefore not specific to Open MPI. Hence, you can use a
different MPI implementation to compile and run these programs if you
Make today an Open MPI day!