#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;
+ long parallel_usecs, parallel_usecs_total = 0, sequential_usecs, sequential_usecs_total = 0;
MPI_Init(&argc, &argv);
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]);
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++) {
-
+ 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));
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
+ // 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");
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(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);
+ 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++) {
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);
+ 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);
+ 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);
}
exit(GETTIMEOFDAY_ERROR);
}
- parallel_usecs =
- (stop_time->tv_sec * 1000000 + stop_time->tv_usec) -
- (start_time->tv_sec * 1000000 + start_time->tv_usec);
+ 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");
exit(GETTIMEOFDAY_ERROR);
}
- sequential_usecs =
- (stop_time->tv_sec * 1000000 + stop_time->tv_usec) -
- (start_time->tv_sec * 1000000 + start_time->tv_usec);
+ 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));
+ 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;
}
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));
+ 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();