#include <mpi.h>#include <stdio.h>intmain(intargc,char**argv){ // Initialize the MPI environmentMPI_Init(NULL,NULL); // Get the number of processesint world_size;MPI_Comm_size(MPI_COMM_WORLD,&world_size); // Get the rank of the processint world_rank;MPI_Comm_rank(MPI_COMM_WORLD,&world_rank); // Get the name of the processorcharprocessor_name[MPI_MAX_PROCESSOR_NAME];int name_len;MPI_Get_processor_name(processor_name,&name_len); // Print off a hello world messageprintf("Hello world from processor %s, rank %d out of %d processors\n", processor_name, world_rank, world_size); // Finalize the MPI environment.MPI_Finalize();}
To compile,
To run interactively,
Note that, there are few mpi modules installed in the system. You can check with module available
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SLURM_JOB_ID = 82971
SLURM_NODELIST = gpu-1-[01-07]
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Hello world from processor gpu-1-01, rank 0 out of 1 processors
Hello world from processor gpu-1-01, rank 0 out of 1 processors
Hello world from processor gpu-1-01, rank 0 out of 1 processors
Hello world from processor gpu-1-01, rank 0 out of 1 processors
Hello world from processor gpu-1-02, rank 0 out of 1 processors
Hello world from processor gpu-1-03, rank 0 out of 1 processors
Hello world from processor gpu-1-02, rank 0 out of 1 processors
Hello world from processor gpu-1-02, rank 0 out of 1 processors
Hello world from processor gpu-1-02, rank 0 out of 1 processors
Hello world from processor gpu-1-05, rank 0 out of 1 processors
Hello world from processor gpu-1-03, rank 0 out of 1 processors
Hello world from processor gpu-1-03, rank 0 out of 1 processors
Hello world from processor gpu-1-03, rank 0 out of 1 processors
Hello world from processor gpu-1-07, rank 0 out of 1 processors
Hello world from processor gpu-1-05, rank 0 out of 1 processors
Hello world from processor gpu-1-05, rank 0 out of 1 processors
Hello world from processor gpu-1-05, rank 0 out of 1 processors
Hello world from processor gpu-1-04, rank 0 out of 1 processors
Hello world from processor gpu-1-07, rank 0 out of 1 processors
Hello world from processor gpu-1-07, rank 0 out of 1 processors
Hello world from processor gpu-1-07, rank 0 out of 1 processors
Hello world from processor gpu-1-04, rank 0 out of 1 processors
Hello world from processor gpu-1-04, rank 0 out of 1 processors
Hello world from processor gpu-1-04, rank 0 out of 1 processors
Hello world from processor gpu-1-06, rank 0 out of 1 processors
Hello world from processor gpu-1-06, rank 0 out of 1 processors
Hello world from processor gpu-1-06, rank 0 out of 1 processors
Hello world from processor gpu-1-06, rank 0 out of 1 processors