MPI 示例

Docklet提供了 MPICH2 软件包。

假定vcluster目前有两个节点 host-0 和 host-1

进入 WEB Terminal。

$ cat /etc/hosts
127.0.0.1       localhost
172.16.0.46     host-0  host-0.tee
172.16.0.45     host-1  host-1.tee

获得节点列表

$ cat /etc/hosts | grep -v localhost | awk '{print $2}'
host-0
host-1

WEB Terminal进入的是host-0，在host-0 上编辑 mpihello.c

#include "mpi.h"
#include <stdio.h>
#include <stdlib.h>
#define  MASTER     0

int main (int argc, char *argv[])
{
    int   numtasks, taskid, len;
    char hostname[MPI_MAX_PROCESSOR_NAME];

    MPI_Init(&argc, &argv);
    MPI_Comm_size(MPI_COMM_WORLD, &numtasks);
    MPI_Comm_rank(MPI_COMM_WORLD,&taskid);
    MPI_Get_processor_name(hostname, &len);
    printf ("Hello from task %d on %s!\n", taskid, hostname);
    if (taskid == MASTER)
        printf("MASTER: Number of MPI tasks is: %d\n",numtasks);
    MPI_Finalize();
    return 0 ;
}

在WEB Terminal中运行:

$ mpicc mpihello.c -o mpihello
$ mpirun -n 2 -hosts host-0,host-1 mpihello
Hello from task 0 on host-0! 
MASTER: Number of MPI tasks is: 2 
Hello from task 1 on host-1!