Mpi examples

docs.it4i/software/mpi/ompi-examples.md

+# OpenMPI Sample Applications
+
+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.
+
+## Examples
+
+There are two MPI examples, each using one of six different MPI interfaces:
+
+**Hello world**
+
+* C:                   [hello_c.c](../../src/ompi/hello_c.c)
+* C++:                 [hello_cxx.cc](../../src/ompi/hello_cxx.cc)
+* Fortran mpif.h:      [hello_mpifh.f](../../src/ompi/hello_mpifh.f)
+* Fortran use mpi:     [hello_usempi.f90](../../src/ompi/hello_usempi.f90)
+* Fortran use mpi_f08: [hello_usempif08.f90](../../src/ompi/hello_usempif08.f90)
+* Java:                [Hello.java](../../src/ompi/Hello.java)
+* C shmem.h:           [hello_oshmem_c.c](../../src/ompi/hello_oshmem_c.c)
+* Fortran shmem.fh:    [hello_oshmemfh.f90](../../src/ompi/hello_oshmemfh.f90)
+
+**Send a trivial message around in a ring**
+
+* C:                   [ring_c.c](../../src/ompi/ring_c.c)
+* C++:                 [ring_cxx.cc](../../src/ompi/ring_cxx.cc)
+* Fortran mpif.h:      [ring_mpifh.f](../../src/ompi/ring_mpifh.f)
+* Fortran use mpi:     [ring_usempi.f90](../../src/ompi/ring_usempi.f90)
+* Fortran use mpi_f08: [ring_usempif08.f90](../../src/ompi/ring_usempif08.f90)
+* Java:                [Ring.java](../../src/ompi/Ring.java)
+* C shmem.h:           [ring_oshmem_c.c](../../src/ompi/ring_oshmem_c.c)
+* Fortran shmem.fh:    [ring_oshmemfh.f90](../../src/ompi/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**
+
+* C:   [connectivity_c.c](../../src/ompi/connectivity_c.c)
+
+## Build Examples
+
+Download [examples](../../src/ompi/ompi.tar.gz).
+
+The Makefile in this directory will build the examples for the supported languages (e.g., if you do not have the Fortran "use mpi" bindings compiled as part of Open MPI, those examples will be skipped).
+
+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 *mpi_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 wish.
+
+```console
+[login@cn204.anselm ]$ tar xvf ompi.tar.gz
+./
+./connectivity_c.c
+./Hello.java
+./ring_mpifh.f
+./hello_oshmem_cxx.cc
+...
+...
+./hello_cxx.cc
+[login@cn204.anselm ]$ ml OpenMPI/2.1.1-GCC-6.3.0-2.27
+[login@cn204.anselm ]$ make
+mpicc -g  hello_c.c  -o hello_c
+mpicc -g  ring_c.c  -o ring_c
+mpicc -g  connectivity_c.c  -o connectivity_c
+mpicc -g  spc_example.c  -o spc_example
+mpic++ -g  hello_cxx.cc  -o hello_cxx
+mpic++ -g  ring_cxx.cc  -o ring_cxx
+mpifort -g  hello_mpifh.f  -o hello_mpifh
+mpifort -g  ring_mpifh.f  -o ring_mpifh
+mpifort -g  hello_usempi.f90  -o hello_usempi
+mpifort -g  ring_usempi.f90  -o ring_usempi
+mpifort -g  hello_usempif08.f90  -o hello_usempif08
+mpifort -g  ring_usempif08.f90  -o ring_usempif08
+mpijavac Hello.java
+mpijavac Ring.java
+shmemcc -g  hello_oshmem_c.c  -o hello_oshmem
+shmemc++ -g  hello_oshmem_cxx.cc  -o hello_oshmemcxx
+shmemcc -g  ring_oshmem_c.c  -o ring_oshmem
+shmemcc -g  oshmem_shmalloc.c  -o oshmem_shmalloc
+shmemcc -g  oshmem_circular_shift.c  -o oshmem_circular_shift
+shmemcc -g  oshmem_max_reduction.c  -o oshmem_max_reduction
+shmemcc -g  oshmem_strided_puts.c  -o oshmem_strided_puts
+shmemcc -g  oshmem_strided_puts.c  -o oshmem_strided_puts
+shmemcc -g  oshmem_symmetric_data.c  -o oshmem_symmetric_data
+shmemfort -g  hello_oshmemfh.f90  -o hello_oshmemfh
+shmemfort -g  ring_oshmemfh.f90  -o ring_oshmemfh
+[login@cn204.anselm ]$ find . -executable -type f
+./hello_oshmem
+./dtrace/myppriv.sh
+./dtrace/partrace.sh
+./oshmem_shmalloc
+./ring_cxx
+./ring_usempi
+./hello_mpifh
+./hello_cxx
+./oshmem_max_reduction
+./oshmem_symmetric_data
+./oshmem_strided_puts
+./hello_usempif08
+./ring_usempif08
+./spc_example
+./hello_oshmemfh
+./ring_oshmem
+./oshmem_circular_shift
+./hello_c
+./ring_c
+./hello_usempi
+./ring_oshmemfh
+./connectivity_c
+./ring_mpifh
+```

docs.it4i/src/ompi/Hello.java

+/*
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+*/
+/*
+ * Author of revised version: Franklyn Pinedo
+ *
+ * Adapted from Source Code in C of Tutorial/User's Guide for MPI by
+ * Peter Pacheco.
+ */
+/*
+ * Copyright (c) 2011      Cisco Systems, Inc.  All rights reserved.
+ *
+ */
+
+import mpi.*;
+
+class Hello {
+    static public void main(String[] args) throws MPIException {
+
+
+	MPI.Init(args);
+
+	int myrank = MPI.COMM_WORLD.getRank();
+	int size = MPI.COMM_WORLD.getSize() ;
+	System.out.println("Hello world from rank " + myrank + " of " + size);
+
+	MPI.Finalize();
+    }
+}

docs.it4i/src/ompi/Ring.java

+/*
+ * Copyright (c) 2011      Cisco Systems, Inc.  All rights reserved.
+ *
+ * Simple ring test program
+ */
+
+import mpi.* ;
+
+class Ring {
+    static public void main(String[] args) throws MPIException {
+
+
+	MPI.Init(args) ;
+
+	int source;  // Rank of sender
+	int dest;    // Rank of receiver
+	int tag=50;  // Tag for messages
+	int next;
+	int prev;
+	int message[] = new int [1];
+
+	int myrank = MPI.COMM_WORLD.getRank() ;
+	int size = MPI.COMM_WORLD.getSize() ;
+
+	/* Calculate the rank of the next process in the ring.  Use the
+	   modulus operator so that the last process "wraps around" to
+	   rank zero. */
+
+	next = (myrank + 1) % size;
+	prev = (myrank + size - 1) % size;
+
+	/* If we are the "master" process (i.e., MPI_COMM_WORLD rank 0),
+	   put the number of times to go around the ring in the
+	   message. */
+
+	if (0 == myrank) {
+	    message[0] = 10;
+
+	    System.out.println("Process 0 sending " + message[0] + " to rank " + next + " (" + size + " processes in ring)");
+	    MPI.COMM_WORLD.send(message, 1, MPI.INT, next, tag);
+	}
+
+	/* Pass the message around the ring.  The exit mechanism works as
+	   follows: the message (a positive integer) is passed around the
+	   ring.  Each time it passes rank 0, it is decremented.  When
+	   each processes receives a message containing a 0 value, it
+	   passes the message on to the next process and then quits.  By
+	   passing the 0 message first, every process gets the 0 message
+	   and can quit normally. */
+
+	while (true) {
+	    MPI.COMM_WORLD.recv(message, 1, MPI.INT, prev, tag);
+
+	    if (0 == myrank) {
+		--message[0];
+		System.out.println("Process 0 decremented value: " + message[0]);
+	    }
+
+	    MPI.COMM_WORLD.send(message, 1, MPI.INT, next, tag);
+	    if (0 == message[0]) {
+		System.out.println("Process " + myrank + " exiting");
+		break;
+	    }
+	}
+
+	/* The last process does one extra send to process 0, which needs
+	   to be received before the program can exit */
+
+	if (0 == myrank) {
+	    MPI.COMM_WORLD.recv(message, 1, MPI.INT, prev, tag);
+	}
+
+	MPI.Finalize();
+    }
+}

docs.it4i/src/ompi/connectivity_c.c

+/*
+ * Copyright (c) 2007      Sun Microsystems, Inc.  All rights reserved.
+ */
+
+/*
+ * Test the connectivity between all processes.
+ */
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <netdb.h>
+#include <unistd.h>
+#include <mpi.h>
+
+int
+main(int argc, char **argv)
+{
+    MPI_Status  status;
+    int         verbose = 0;
+    int         rank;
+    int         np;        /* number of processes in job */
+    int         peer;
+    int         i;
+    int         j;
+    int         length;
+    char        name[MPI_MAX_PROCESSOR_NAME+1];
+
+    MPI_Init(&argc, &argv);
+    MPI_Comm_rank(MPI_COMM_WORLD, &rank);
+    MPI_Comm_size(MPI_COMM_WORLD, &np);
+
+    /*
+     * If we cannot get the name for whatever reason, just
+     * set it to unknown. */
+    if (MPI_SUCCESS != MPI_Get_processor_name(name, &length)) {
+        strcpy(name, "unknown");
+    }
+
+    if (argc>1 && strcmp(argv[1], "-v")==0)
+        verbose = 1;
+
+    for (i=0; i<np; i++) {
+        if (rank==i) {
+            /* rank i sends to and receives from each higher rank */
+            for(j=i+1; j<np; j++) {
+                if (verbose)
+                    printf("checking connection between rank %d on %s and rank %-4d\n",
+                           i, name, j);
+                MPI_Send(&rank, 1, MPI_INT, j, rank, MPI_COMM_WORLD);
+                MPI_Recv(&peer, 1, MPI_INT, j, j, MPI_COMM_WORLD, &status);
+            }
+        } else if (rank>i) {
+            /* receive from and reply to rank i */
+            MPI_Recv(&peer, 1, MPI_INT, i, i, MPI_COMM_WORLD, &status);
+            MPI_Send(&rank, 1, MPI_INT, i, rank, MPI_COMM_WORLD);
+        }
+    }
+
+    MPI_Barrier(MPI_COMM_WORLD);
+    if (rank==0)
+        printf("Connectivity test on %d processes PASSED.\n", np);
+
+    MPI_Finalize();
+    return 0;
+}

docs.it4i/src/ompi/hello_c.c

+/*
+ * Copyright (c) 2004-2006 The Trustees of Indiana University and Indiana
+ *                         University Research and Technology
+ *                         Corporation.  All rights reserved.
+ * Copyright (c) 2006      Cisco Systems, Inc.  All rights reserved.
+ *
+ * Sample MPI "hello world" application in C
+ */
+
+#include <stdio.h>
+#include "mpi.h"
+
+int main(int argc, char* argv[])
+{
+    int rank, size, len;
+    char version[MPI_MAX_LIBRARY_VERSION_STRING];
+
+    MPI_Init(&argc, &argv);
+    MPI_Comm_rank(MPI_COMM_WORLD, &rank);
+    MPI_Comm_size(MPI_COMM_WORLD, &size);
+    MPI_Get_library_version(version, &len);
+    printf("Hello, world, I am %d of %d, (%s, %d)\n",
+           rank, size, version, len);
+    MPI_Finalize();
+
+    return 0;
+}

docs.it4i/src/ompi/hello_cxx.cc

+//
+// Copyright (c) 2004-2006 The Trustees of Indiana University and Indiana
+//                         University Research and Technology
+//                         Corporation.  All rights reserved.
+// Copyright (c) 2006      Cisco Systems, Inc.  All rights reserved.
+//
+// Sample MPI "hello world" application in C++
+//
+// NOTE: The MPI C++ bindings were deprecated in MPI-2.2 and removed
+// from the standard in MPI-3.  Open MPI still provides C++ MPI
+// bindings, but they are no longer built by default (and may be
+// removed in a future version of Open MPI).  You must
+// --enable-mpi-cxx when configuring Open MPI to enable the MPI C++
+// bindings.
+//
+
+#include "mpi.h"
+#include <iostream>
+
+int main(int argc, char **argv)
+{
+    int rank, size, len;
+    char version[MPI_MAX_LIBRARY_VERSION_STRING];
+
+    MPI::Init();
+    rank = MPI::COMM_WORLD.Get_rank();
+    size = MPI::COMM_WORLD.Get_size();
+    MPI_Get_library_version(version, &len);
+    std::cout << "Hello, world!  I am " << rank << " of " << size
+              << "(" << version << ", " << len << ")" << std::endl;
+    MPI::Finalize();
+
+    return 0;
+}

docs.it4i/src/ompi/hello_mpifh.f

+C
+C Copyright (c) 2004-2006 The Trustees of Indiana University and Indiana
+C                         University Research and Technology
+C                         Corporation.  All rights reserved.
+C Copyright (c) 2006-2015 Cisco Systems, Inc.  All rights reserved.
+C $COPYRIGHT$
+C
+C Sample MPI "hello world" application using the Fortran mpif.h
+C bindings.
+C
+        program main
+        implicit none
+        include 'mpif.h'
+        integer ierr, rank, size, len
+        character(len=MPI_MAX_LIBRARY_VERSION_STRING) version
+
+        call MPI_INIT(ierr)
+        call MPI_COMM_RANK(MPI_COMM_WORLD, rank, ierr)
+        call MPI_COMM_SIZE(MPI_COMM_WORLD, size, ierr)
+        call MPI_GET_LIBRARY_VERSION(version, len, ierr)
+
+        write(*, '("Hello, world, I am ", i2, " of ", i2, ": ", a)')
+     &        rank, size, version
+
+        call MPI_FINALIZE(ierr)
+
+        end

docs.it4i/src/ompi/hello_oshmem_c.c

+/*
+ * Copyright (c) 2014      Mellanox Technologies, Inc.
+ *                         All rights reserved.
+ * Copyright (c) 2015 Cisco Systems, Inc.  All rights reserved.
+ * $COPYRIGHT$
+ *
+ * Additional copyrights may follow
+ *
+ * $HEADER$
+ */
+
+#include <stdio.h>
+#include "shmem.h"
+
+#if !defined(OSHMEM_SPEC_VERSION) || OSHMEM_SPEC_VERSION < 10200
+#error This application uses API 1.2 and up
+#endif
+
+int main(int argc, char* argv[])
+{
+    int proc, nproc;
+    char name[SHMEM_MAX_NAME_LEN];
+    int major, minor;
+
+    shmem_init();
+    nproc = shmem_n_pes();
+    proc = shmem_my_pe();
+    shmem_info_get_name(name);
+    shmem_info_get_version(&major, &minor);
+
+    printf("Hello, world, I am %d of %d: %s (version: %d.%d)\n",
+           proc, nproc, name, major, minor);
+    shmem_finalize();
+
+    return 0;
+}

docs.it4i/src/ompi/hello_oshmem_cxx.cc

+/*
+ * Copyright (c) 2014      Mellanox Technologies, Inc.
+ *                         All rights reserved.
+ * Copyright (c) 2015      Cisco Systems, Inc.  All rights reserved.
+ * Copyright (c) 2017      Research Organization for Information Science
+ *                         and Technology (RIST). All rights reserved.
+ * $COPYRIGHT$
+ *
+ * Additional copyrights may follow
+ *
+ * $HEADER$
+ */
+
+#include <iostream>
+#include "shmem.h"
+
+#if !defined(OSHMEM_SPEC_VERSION) || OSHMEM_SPEC_VERSION < 10200
+#error This application uses API 1.2 and up
+#endif
+
+int main(int argc, char* argv[])
+{
+    int proc, nproc;
+    char name[SHMEM_MAX_NAME_LEN];
+    int major, minor;
+
+    shmem_init();
+    nproc = shmem_n_pes();
+    proc = shmem_my_pe();
+    shmem_info_get_name(name);
+    shmem_info_get_version(&major, &minor);
+
+    std::cout << "Hello, world, I am " << proc << " of " << nproc << ": " << name
+              << " (version: " << major << "." << minor << ")" << std::endl;
+
+    shmem_finalize();
+
+    return 0;
+}

docs.it4i/src/ompi/hello_oshmemfh.f90

+!
+! Copyright (c) 2014      Mellanox Technologies, Inc.
+!                         All rights reserved.
+! Copyright (c) 2014-2015 Cisco Systems, Inc.  All rights reserved.
+! $COPYRIGHT$
+!
+! Additional copyrights may follow
+!
+! $HEADER$
+!
+program hello_oshmem
+    implicit none
+    include 'shmem.fh'
+
+    integer proc, nproc
+    integer shmem_my_pe, shmem_n_pes
+    integer major, minor, len
+    character(len=SHMEM_MAX_NAME_LEN) name
+
+    call SHMEM_INIT()
+    proc = SHMEM_MY_PE()
+    nproc = SHMEM_N_PES()
+    call SHMEM_INFO_GET_VERSION(major, minor)
+    call SHMEM_INFO_GET_NAME(name)
+
+    write(*, '("Hello, world, I am ", i2, " of ", i2, ": (version: ", i0, ".", i0, ")")') proc, nproc, major, minor
+    call SHMEM_FINALIZE()
+
+end program hello_oshmem

docs.it4i/src/ompi/hello_usempi.f90

+!
+! Copyright (c) 2004-2006 The Trustees of Indiana University and Indiana
+!                         University Research and Technology
+!                         Corporation.  All rights reserved.
+! Copyright (c) 2004-2005 The Regents of the University of California.
+!                         All rights reserved.
+! Copyright (c) 2006-2015 Cisco Systems, Inc.  All rights reserved.
+! $COPYRIGHT$
+!
+! Sample MPI "hello world" application using the Fortran mpi module
+! bindings.
+!
+program main
+    use mpi
+    implicit none
+    integer :: ierr, rank, size, len
+    character(len=MPI_MAX_LIBRARY_VERSION_STRING) :: version
+
+    call MPI_INIT(ierr)
+    call MPI_COMM_RANK(MPI_COMM_WORLD, rank, ierr)
+    call MPI_COMM_SIZE(MPI_COMM_WORLD, size, ierr)
+    call MPI_GET_LIBRARY_VERSION(version, len, ierr)
+
+    write(*, '("Hello, world, I am ", i2, " of ", i2, ": ", a)') &
+          rank, size, version
+
+    call MPI_FINALIZE(ierr)
+end

docs.it4i/src/ompi/hello_usempif08.f90

+! -*- f90 -*-
+!
+! Copyright (c) 2004-2006 The Trustees of Indiana University and Indiana
+!                         University Research and Technology
+!                         Corporation.  All rights reserved.
+! Copyright (c) 2004-2005 The Regents of the University of California.
+!                         All rights reserved.
+! Copyright (c) 2006-2015 Cisco Systems, Inc.  All rights reserved.
+! Copyright (c) 2009-2012 Los Alamos National Security, LLC.
+!                         All rights reserved.
+! $COPYRIGHT$
+!
+! Sample MPI "hello world" application using the Fortran mpi_f08
+! module bindings.
+!
+program main
+    use mpi_f08
+    implicit none
+    integer :: rank, size, len
+    character(len=MPI_MAX_LIBRARY_VERSION_STRING) :: version
+
+    call MPI_INIT()
+    call MPI_COMM_RANK(MPI_COMM_WORLD, rank)
+    call MPI_COMM_SIZE(MPI_COMM_WORLD, size)
+    call MPI_GET_LIBRARY_VERSION(version, len)
+
+    write(*, '("Hello, world, I am ", i2, " of ", i2, ": ", a)') &
+          rank, size, version
+
+    call MPI_FINALIZE()
+end

docs.it4i/src/ompi/oshmem_circular_shift.c

+/*
+ * Copyright (c) 2014-2016 Mellanox Technologies, Inc.
+ *                         All rights reserved.
+ * $COPYRIGHT$
+ *
+ * Additional copyrights may follow
+ *
+ * $HEADER$
+ */
+
+#include <stdio.h>
+#include <shmem.h>
+
+int main (void)
+{
+    static int aaa, bbb;
+    int num_pes, my_pe, peer;
+
+    shmem_init();
+
+    num_pes = shmem_n_pes();
+    my_pe = shmem_my_pe();
+
+    peer = (my_pe + 1) % num_pes;
+
+    printf("Process %d gets message from %d (%d processes in ring)\n", my_pe, peer, num_pes);
+    shmem_int_get(&aaa, &bbb, 1, peer);
+
+    shmem_barrier_all();
+    printf("Process %d exiting\n", my_pe);
+    shmem_finalize();
+
+    return 0;
+}
+

docs.it4i/src/ompi/oshmem_max_reduction.c

+/*
+ * Copyright (c) 2014-2016 Mellanox Technologies, Inc.
+ *                         All rights reserved.
+ * $COPYRIGHT$
+ *
+ * Additional copyrights may follow
+ *
+ * $HEADER$
+ *
+ * reduce [0,1,2] + _my_pe() across 4 PEs with MAX()
+ */
+
+#include <stdio.h>
+#include <string.h>
+