root/orte/test/mpi/reduce-hang.c

DEFINITIONS

1. main

   1 #include <mpi.h>
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 
   5 int main(int argc, char *argv[])
   6 {
   7     long count = 0;
   8     int i = 8, j;
   9     int self;
  10     int do_barrier = 0;
  11 int k;
  12 double pi;
  13 
  14     if (getenv("DO_BARRIER")) {
  15         do_barrier = 1;
  16     }
  17 
  18     MPI_Init(&argc, &argv);
  19     MPI_Comm_rank(MPI_COMM_WORLD, &self);
  20     while (1) {
  21 #if 0
  22 for (k=0; k < (7-self)*1000; k++) {
  23 pi = 3.14159 * 18.0 / 35.3;
  24 }
  25 #endif
  26         MPI_Reduce(&i, &j, 1, MPI_INT, MPI_SUM, 0, MPI_COMM_WORLD);
  27         if (do_barrier) {
  28             MPI_Barrier(MPI_COMM_WORLD);
  29         }
  30         if (0 == (++count % 10000)) {
  31             fprintf(stderr, "%d still going at %ld\n", self, count);
  32         }
  33     }
  34     MPI_Finalize();
  35 
  36     return 0;
  37 }