C++ MPI_Allreduce中的致命错误

我需要使用MPICH创建集群。在本例中，我首先在一台机器上尝试了这些示例，这些都是预期的工作。然后我根据这个创建了集群，并运行下面给出的示例，它可以正常工作

#include <stdio.h>
#include <mpi.h>

int main(int argc, char** argv) {
 int myrank, nprocs;

 MPI_Init(&argc, &argv);
 MPI_Comm_size(MPI_COMM_WORLD, &nprocs);
 MPI_Comm_rank(MPI_COMM_WORLD, &myrank);

 printf("Hello from processor %d of %d\n", myrank, nprocs);

 MPI_Finalize();
 return 0;

接下来我运行了这个例子，但当时我得到了这个错误。不知道哪里出了问题

    Fatal error in MPI_Allreduce: A process has failed, error stack:
    MPI_Allreduce(861)........: MPI_Allreduce(sbuf=0x7ffff0f55630, rbuf=0x7ffff0f55634, count=1, MPI_FLOAT, MPI_SUM, MPI_COMM_WORLD) failed
    MPIR_Allreduce_impl(719)..:
    MPIR_Allreduce_intra(362).:
    dequeue_and_set_error(888): Communication error with rank 1

    ===================================================================================
    =   BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES
    =   EXIT CODE: 1
    =   CLEANING UP REMAINING PROCESSES
    =   YOU CAN IGNORE THE BELOW CLEANUP MESSAGES
    ===================================================================================
    [proxy:0:1@ce-412] HYD_pmcd_pmip_control_cmd_cb (./pm/pmiserv/pmip_cb.c:886): assert (!closed) failed
    [proxy:0:1@ce-412] HYDT_dmxu_poll_wait_for_event (./tools/demux/demux_poll.c:77): callback returned error status
    [proxy:0:1@ce-412] main (./pm/pmiserv/pmip.c:206): demux engine error waiting for event
    [mpiexec@ce-411] HYDT_bscu_wait_for_completion (./tools/bootstrap/utils/bscu_wait.c:76): one of the processes terminated badly; aborting
    [mpiexec@ce-411] HYDT_bsci_wait_for_completion (./tools/bootstrap/src/bsci_wait.c:23): launcher returned error waiting for completion
    [mpiexec@ce-411] HYD_pmci_wait_for_completion (./pm/pmiserv/pmiserv_pmci.c:217): launcher returned error waiting for completion
    [mpiexec@ce-411] main (./ui/mpich/mpiexec.c:331): process manager error waiting for completion

---

是的，正如@Alexey提到的，这完全是一个网络错误。以下是我所做的使这项工作得以实施的事情

一,。将主机文件导出为HYDRA_host_文件，以了解MPICH的详细信息：

最后是一个命令，它为我提供了集群节点之间的正确连接

  mpiexec -launcher fork -disable-hostname-propagation  -f machinefile -np 4 ./Test

---

根据秩1消息的通信错误，秩0的主节点无法连接到秩1的节点，因此您应该查看该方向。您可以尝试使用简单的MPI_发送和MPI_接收从根目录ping节点1。这些方法也不起作用，因此肯定是网络设置错误。您是否尝试检查以下内容？

    export HYDRA_HOST_FILE=<path_to_host_file>/hosts

   -disable-hostname-propagation

  mpiexec -launcher fork -disable-hostname-propagation  -f machinefile -np 4 ./Test