openmpi/examples/spc_example.c

123 lines
3.9 KiB
C

/*
* Copyright (c) 2018-2020 The University of Tennessee and The University
* of Tennessee Research Foundation. All rights
* reserved.
*
* Simple example usage of SPCs through MPI_T.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "mpi.h"
/* Sends 'num_messages' messages of 'message_size' bytes from rank 0 to rank 1.
* All messages are send synchronously and with the same tag in MPI_COMM_WORLD.
*/
void message_exchange(int num_messages, int message_size)
{
int i, rank;
/* Use calloc to initialize data to 0's */
char *data = (char*)calloc(message_size, sizeof(char));
MPI_Status status;
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
if(rank == 0) {
for(i = 0; i < num_messages; i++)
MPI_Send(data, message_size, MPI_BYTE, 1, 123, MPI_COMM_WORLD);
} else if(rank == 1) {
for(i = 0; i < num_messages; i++)
MPI_Recv(data, message_size, MPI_BYTE, 0, 123, MPI_COMM_WORLD, &status);
}
free(data);
}
int main(int argc, char **argv)
{
int num_messages, message_size, rc;
if(argc < 3) {
printf("Usage: mpirun -np 2 --mca mpi_spc_attach all --mca mpi_spc_dump_enabled true ./spc_example [num_messages] [message_size]\n");
return -1;
} else {
num_messages = atoi(argv[1]);
message_size = atoi(argv[2]);
}
int i, rank, size, provided, num, name_len, desc_len, verbosity, bind, var_class, readonly, continuous, atomic, count, index;
MPI_Datatype datatype;
MPI_T_enum enumtype;
MPI_Comm comm;
char name[256], description[256];
/* Counter names to be read by ranks 0 and 1 */
char *counter_names[] = {"runtime_spc_OMPI_BYTES_SENT_USER",
"runtime_spc_OMPI_BYTES_RECEIVED_USER" };
MPI_Init(NULL, NULL);
MPI_T_init_thread(MPI_THREAD_SINGLE, &provided);
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
MPI_Comm_size(MPI_COMM_WORLD, &size);
if(size != 2) {
fprintf(stderr, "ERROR: This test should be run with two MPI processes.\n");
MPI_Abort(MPI_COMM_WORLD, -1);
}
/* Determine the MPI_T pvar indices for the OMPI_BYTES_SENT/RECIEVED_USER SPCs */
index = -1;
MPI_T_pvar_get_num(&num);
for(i = 0; i < num; i++) {
name_len = desc_len = 256;
rc = PMPI_T_pvar_get_info(i, name, &name_len, &verbosity,
&var_class, &datatype, &enumtype, description, &desc_len, &bind,
&readonly, &continuous, &atomic);
if( MPI_SUCCESS != rc )
continue;
if(strcmp(name, counter_names[rank]) == 0) {
index = i;
printf("[%d] %s -> %s\n", rank, name, description);
}
}
/* Make sure we found the counters */
if(index == -1) {
fprintf(stderr, "ERROR: Couldn't find the appropriate SPC counter in the MPI_T pvars.\n");
MPI_Abort(MPI_COMM_WORLD, -1);
}
int ret;
long long value;
MPI_T_pvar_session session;
MPI_T_pvar_handle handle;
/* Create the MPI_T sessions/handles for the counters and start the counters */
ret = MPI_T_pvar_session_create(&session);
ret = MPI_T_pvar_handle_alloc(session, index, NULL, &handle, &count);
ret = MPI_T_pvar_start(session, handle);
message_exchange(num_messages, message_size);
ret = MPI_T_pvar_read(session, handle, &value);
/* Print the counter values in order by rank */
for(i = 0; i < 2; i++) {
if(i == rank) {
printf("[%d] Value Read: %lld\n", rank, value);
fflush(stdout);
}
MPI_Barrier(MPI_COMM_WORLD);
}
/* Stop the MPI_T session, free the handle, and then free the session */
ret = MPI_T_pvar_stop(session, handle);
ret = MPI_T_pvar_handle_free(session, &handle);
ret = MPI_T_pvar_session_free(&session);
MPI_T_finalize();
MPI_Finalize();
return 0;
}