MPI意外的输出 [英] MPI Unexpected output

问题描述

我在读和教程练习MPI程序。在那里，我看到了寻找过程的秩的一个例子。但是，同样的例子是我的机器（Ubuntu的10.04）上提供不同的输出..
下面是节目

I was reading and practicing MPI programs from a tutorial. There I saw an example of finding a rank of a process. But the same example is giving different output on my machine(Ubuntu 10.04).. Here is the program

 #include <stdio.h>
 #include <mpi.h> 
main(int argc, char **argv)
{
  int ierr, num_procs, my_id;

  ierr = MPI_Init(&argc, &argv);

  /* find out MY process ID, and how many processes were started. */

  ierr = MPI_Comm_rank(MPI_COMM_WORLD, &my_id);
  ierr = MPI_Comm_size(MPI_COMM_WORLD, &num_procs);

  printf("Hello world! I'm process %i out of %i processes\n", 
     my_id, num_procs);

  ierr = MPI_Finalize();
}

根据本教程的预期成果是

The expected output according to the tutorial is

期望输出：

Hello world! I'm process 0 out of 4 processes.
Hello world! I'm process 2 out of 4 processes.
Hello world! I'm process 1 out of 4 processes.
Hello world! I'm process 3 out of 4 processes.

输出，我正在

Hello world! I'm process 0 out of 1 processes
Hello world! I'm process 0 out of 1 processes
Hello world! I'm process 0 out of 1 processes
Hello world! I'm process 0 out of 1 processes

我的机器采用了英特尔酷睿i3，戴尔Inspiron并有Ubuntu的10.04 OS.Help我解决问题。

My machine uses intel i3,Dell Inspiron and is having Ubuntu 10.04 OS.Help me resolving the problem.

推荐答案

我刚才编译和在我的Ubuntu运行您的程序：

I have just compiled and run your program on my Ubuntu:

tom@tom-ThinkPad-T500:~/MPI_projects/Start/net2/net2/bin/Debug$ mpirun -n 6 ./output
Hello world! I'm process 3 out of 6 processes
Hello world! I'm process 4 out of 6 processes
Hello world! I'm process 0 out of 6 processes
Hello world! I'm process 2 out of 6 processes
Hello world! I'm process 1 out of 6 processes
Hello world! I'm process 5 out of 6 processes

您的可执行文件输入文件夹，然后运行：

Enter the folder with your executable file and run:

的mpirun -np 2 ./output

或

的mpirun -np 6 ./output

-np修改称为进程数的标志（ http://linux.die.net /人/ 1 /的mpirun ）。

the flag -np modifies the number of called processes (http://linux.die.net/man/1/mpirun).

您还可以运行的mpirun 不带任何标志显示很多有用的信息。

You can also run mpirun without any flags to display lots of useful info.

另一个有趣的命令是的mpirun -info ，它会显示打印MPI构建信息。

Another interesting command is mpirun -info, which will show print MPI build information.

这是我的输出的第一部分：

This is the first part of my output:

tom@tom-ThinkPad-T500:~/MPI_projects/Start/net2/net2/bin/Debug$ mpirun -info
HYDRA build details:
Version:                                 1.4.1
Release Date:                            Wed Aug 24 14:40:04 CDT 2011

最后的手段是重新安装或更新使用MPI例如，下面的命令：命令和apt-get安装libcr-dev的MPICH2 MPICH2-DOC

这篇关于MPI意外的输出的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！