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这个问题与这个问题有关：MPI and D: Linker Options

我正在尝试让 MPI 从 D 中工作。在网上可以找到几篇文章，但我发现没有一个确实有效......所以这是我到目前为止所做的：

我从这里https://github.com/1100110/OpenMPI/blob/master/mpi.d获取了 mpi.d并设置了一个最小程序：

import mpi;
import std.stdio;

void* MPI_COMM_WORLD = cast(void*)0;

int main(string[] args)
{

  int rank, size;
  int argc = cast(int)args.length;
  char *** argv = cast(char***)&args;


  MPI_Init (&argc, argv);   /* starts MPI */
  MPI_Comm_rank (MPI_COMM_WORLD, &rank);    /* get current process id */
  MPI_Comm_size (MPI_COMM_WORLD, &size);    /* get number of processes */
  writefln( "Hello world from process %d of %d", rank, size );
  MPI_Finalize();

  return 0;
}

我编译

dmd test_mpi.d -L-L/usr/lib/openmpi -L-lmpi -L-ldl -L-lhwloc

或者

gdc test_mpi.d -pthread -L/usr/lib/openmpi -lmpi -ldl -lhwloc -o test_mpi

并运行

mpirun -n 2 ./test_mpi

这是我得到的错误：

[box:1871] *** An error occurred in MPI_Comm_rank
[box:1871] *** on communicator MPI_COMM_WORLD
[box:1871] *** MPI_ERR_COMM: invalid communicator
[box:1871] *** MPI_ERRORS_ARE_FATAL: your MPI job will now abort
--------------------------------------------------------------------------
mpirun has exited due to process rank 0 with PID 1870 on
node bermuda-iii exiting improperly. There are two reasons this could occur:

1. this process did not call "init" before exiting, but others in
the job did. This can cause a job to hang indefinitely while it waits
for all processes to call "init". By rule, if one process calls "init",
then ALL processes must call "init" prior to termination.

2. this process called "init", but exited without calling "finalize".
By rule, all processes that call "init" MUST call "finalize" prior to
exiting or it will be considered an "abnormal termination"

This may have caused other processes in the application to be
terminated by signals sent by mpirun (as reported here).
--------------------------------------------------------------------------
[box:01869] 1 more process has sent help message help-mpi-errors.txt / mpi_errors_are_fatal
[box:01869] Set MCA parameter "orte_base_help_aggregate" to 0 to see all help / error messages

显然我确实调用了 MPI_Init 和 MPI_Finalize。那么我错过了什么？

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2 回答 2

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在 Open MPI C 中，通信器句柄是指向实际通信器结构的指针。MPI_COMM_WORLD是指向预先创建的世界通信器结构的指针，而不是您定义的 NULL 指针。这就是 Open MPI 在调用中中止的原因MPI_COMM_RANK- 它相当于MPI_Comm_rank(NULL, &rank)在 C中调用。

如果您查看第 808 行，mpi.d您会注意到MPI_COMM_WORLD已定义为：

MPI_COMM_WORLD      = cast(void*) &(ompi_mpi_comm_world),

因此，如果您删除重新定义的行，您的代码应该可以工作MPI_COMM_WORLD。

于 2013-02-06T16:53:42.793 回答
3

你没有string[]向右投射char***。你应该这样做：

import std.string, std.algorithm, std.array;

char** argv = cast(char**)map!(toStringz)(args).array.ptr;
MPI_Init (&argc, &argv);

以下是它的工作原理：

  • toStringz每个args元素上的映射。

  • 因为 map 返回范围，所以我们使用array它的数组。

  • 获取数组指针。

于 2013-02-06T14:56:15.660 回答