-/* Copyright (c) 2009-2010, 2013-2014. The SimGrid Team.
- * All rights reserved. */
-
-/* This program is free software; you can redistribute it and/or modify it
- * under the terms of the license (GNU LGPL) which comes with this package. */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <ctype.h>
-#include <mpi.h>
-#include <xbt/str.h>
-
-#define ITERATIONS 10
-#define USAGE_ERROR 1
-#define SANITY_ERROR 2
-#define GETTIMEOFDAY_ERROR 3
-
-int main(int argc, char *argv[])
-{
- int size, rank;
- int N, n, i, j, k, current_iteration, successful_iterations = 0;
- double *matrix = NULL, *vector = NULL, *vcalc, *vcheck;
- MPI_Status status;
- struct timeval *start_time = NULL, *stop_time = NULL;
- long parallel_usecs, parallel_usecs_total = 0, sequential_usecs, sequential_usecs_total = 0;
-
- MPI_Init(&argc, &argv);
-
- MPI_Comm_rank(MPI_COMM_WORLD, &rank);
- MPI_Comm_size(MPI_COMM_WORLD, &size);
-
- if (0 == rank) {
- // root node parses cmdline args
- if (2 > argc || !isdigit(*argv[1])) {
- printf("usage:\n%s <size>\n", argv[0]);
- MPI_Abort(MPI_COMM_WORLD, USAGE_ERROR);
- exit(USAGE_ERROR);
- }
-
- N = xbt_str_parse_int(argv[1], "Invalid size: %s");
-
- start_time = (struct timeval *) malloc(sizeof(struct timeval));
- stop_time = (struct timeval *) malloc(sizeof(struct timeval));
- }
-
- for (current_iteration = 0; current_iteration < ITERATIONS; current_iteration++) {
- if (0 == rank) {
- matrix = (double *) malloc(N * N * sizeof(double));
- vector = (double *) malloc(N * sizeof(double));
-
- for (i = 0; i < N * N; i++) {
- matrix[i] = (double) rand() / ((double) RAND_MAX + 1);
- }
-
- for (i = 0; i < N; i++) {
- vector[i] = (double) rand() / ((double) RAND_MAX + 1);
- }
-
- // for the sake of argument, the parallel algorithm begins when the root node begins to transmit the matrix to the
- // workers.
- if (-1 == gettimeofday(start_time, NULL)) {
- printf("couldn't set start_time on node 0!\n");
- MPI_Abort(MPI_COMM_WORLD, GETTIMEOFDAY_ERROR);
- exit(GETTIMEOFDAY_ERROR);
- }
-
- for (i = 1; i < size; i++) {
- MPI_Send(&N, 1, MPI_INT, i, 0, MPI_COMM_WORLD);
- }
- } else {
- MPI_Recv(&N, 1, MPI_INT, 0, 0, MPI_COMM_WORLD, &status);
- }
-
- // this algorithm uses at most N processors...
- if (rank < N) {
- if (size > N)
- size = N;
- n = N / size + ((rank < (N % size)) ? 1 : 0);
-
- if (0 == rank) {
- for (i = 1, j = n; i < size && j < N; i++, j += k) {
- k = N / size + ((i < (N % size)) ? 1 : 0);
- MPI_Send(matrix + N * j, N * k, MPI_DOUBLE, i, 0, MPI_COMM_WORLD);
- MPI_Send(vector, N, MPI_DOUBLE, i, 0, MPI_COMM_WORLD);
- }
-
- // sanity check
-#ifdef DEBUG
- if (i != size || j != N) {
- printf("index calc error: i = %d, size = %d, j = %d, N = %d\n", i, size, j, N);
- MPI_Abort(MPI_COMM_WORLD, SANITY_ERROR);
- exit(SANITY_ERROR);
- }
-#endif
-
- vcalc = (double *) malloc(N * sizeof(double));
- } else {
- matrix = (double *) malloc(N * n * sizeof(double));
- vector = (double *) malloc(N * sizeof(double));
- vcalc = (double *) malloc(n * sizeof(double));
-
- MPI_Recv(matrix, N * n, MPI_DOUBLE, 0, 0, MPI_COMM_WORLD, &status);
- MPI_Recv(vector, N, MPI_DOUBLE, 0, 0, MPI_COMM_WORLD, &status);
- }
-
- for (i = 0; i < n; i++) {
- vcalc[i] = 0.0;
- for (j = 0; j < N; j++) {
- vcalc[i] += matrix[N * i + j] * vector[j];
- }
- }
-
- if (0 != rank) {
- MPI_Send(vcalc, n, MPI_DOUBLE, 0, 0, MPI_COMM_WORLD);
- } else {
- for (i = 1, j = n; i < size && j < N; i++, j += k) {
- k = N / size + ((i < (N % size)) ? 1 : 0);
- MPI_Recv(vcalc + j, k, MPI_DOUBLE, i, 0, MPI_COMM_WORLD, &status);
- }
-
- // sanity check
-#ifdef DEBUG
- if (i != size || j != N) {
- printf("index calc error 2: i = %d, size = %d, j = %d, N = %d\n", i, size, j, N);
- MPI_Abort(MPI_COMM_WORLD, SANITY_ERROR);
- exit(SANITY_ERROR);
- }
-#endif
-
- if (-1 == gettimeofday(stop_time, NULL)) {
- printf("couldn't set stop_time on node 0!\n");
- MPI_Abort(MPI_COMM_WORLD, GETTIMEOFDAY_ERROR);
- exit(GETTIMEOFDAY_ERROR);
- }
-
- parallel_usecs = (stop_time->tv_sec * 1000000 + stop_time->tv_usec) -
- (start_time->tv_sec * 1000000 + start_time->tv_usec);
-
- if (-1 == gettimeofday(start_time, NULL)) {
- printf("couldn't set start_time on node 0!\n");
- MPI_Abort(MPI_COMM_WORLD, GETTIMEOFDAY_ERROR);
- exit(GETTIMEOFDAY_ERROR);
- }
- // calculate serially
- vcheck = (double *) malloc(N * sizeof(double));
- for (i = 0; i < N; i++) {
- vcheck[i] = 0.0;
- for (j = 0; j < N; j++) {
- vcheck[i] += matrix[N * i + j] * vector[j];
- }
- }
-
- if (-1 == gettimeofday(stop_time, NULL)) {
- printf("couldn't set stop_time on node 0!\n");
- MPI_Abort(MPI_COMM_WORLD, GETTIMEOFDAY_ERROR);
- exit(GETTIMEOFDAY_ERROR);
- }
-
- sequential_usecs = (stop_time->tv_sec * 1000000 + stop_time->tv_usec) -
- (start_time->tv_sec * 1000000 + start_time->tv_usec);
-
- // verify correctness
- for (i = 0; i < N && vcalc[i] == vcheck[i]; i++);
-
- printf("prog: blocking, i: %d ", current_iteration);
-
- if (i == N) {
- printf("ptime: %ld us, stime: %ld us, speedup: %.3f, nodes: %d, efficiency: %.3f\n",
- parallel_usecs, sequential_usecs, (double) sequential_usecs / (double) parallel_usecs, size,
- (double) sequential_usecs / ((double) parallel_usecs * (double) size));
-
- parallel_usecs_total += parallel_usecs;
- sequential_usecs_total += sequential_usecs;
- successful_iterations++;
- } else {
- printf("parallel calc != serial calc, ");
- }
-
- free(vcheck);
- }
-
- free(matrix);
- free(vector);
- free(vcalc);
- }
- }
-
- if (0 == rank) {
- printf("prog: blocking, ");
- if (0 < successful_iterations) {
- printf("iterations: %d, avg. ptime: %.3f us, avg. stime: %.3f us, avg. speedup: %.3f, nodes: %d, avg. efficiency: %.3f\n",
- successful_iterations, (double) parallel_usecs_total / (double) successful_iterations,
- (double) sequential_usecs_total / (double) successful_iterations,
- (double) sequential_usecs_total / (double) parallel_usecs_total, size,
- (double) sequential_usecs_total / ((double) parallel_usecs_total * (double) size));
- } else {
- printf("no successful iterations!\n");
- }
-
- free(start_time);
- free(stop_time);
- }
-
- MPI_Finalize();
-
- return 0;
-}
