[R] doMPI: script hangs on closeCluster

[Loris Bennett]

Hi,

On Linux with R 3.5.1 and OpenMPI 2.1.0 I have built Rmpi and can run a
simple example just using Rmpi and printing out the rank of each worker.

However, when I try to use doMPI by running the following

  library(Rmpi)
  library(doMPI)
  cl <- startMPIcluster(count=2)
  registerDoMPI(cl)
  clusterSize(cl)
  closeCluster(cl)
  mpi.quit()

with

  mpirun -np 1 --mca mpi_warn_on_fork 0 R --no-save -f mwe.r

I get the following output

  > library("Rmpi")
  > library(doMPI)
  Loading required package: foreach
  Loading required package: iterators
  > cl <- startMPIcluster(count=2)
  	2 slaves are spawned successfully. 0 failed.
  > registerDoMPI(cl)
  > clusterSize(cl)
  [1] 2
  > closeCluster(cl)

but the program hangs and I have to end it with Ctl-C.

Can anyone shed any light on what might be wrong?

Cheers,

Loris

-- 
Dr. Loris Bennett (Mr.)
ZEDAT, Freie Universität Berlin         Email loris.bennett using fu-berlin.de