[jbae]

Hi,

I am trying to run multiple runs of SU2 using the python wrapper. However, whenever I try to pass a pre-set communicator that is not MPI_COMM_WORLD as the communicator, the program seems to hang. Does anyone have an idea why this might be?

Here is a simplified version of the code I'm trying to run:

import sys
import shutil
import pysu2 as pysu2          # imports the SU2 adjoint-wrapped module
from mpi4py import MPI

def main(comm):

  # Define the input file names
  flow_filename = "config.cfg"

  # Initialize the flow driver of SU2, this includes solver preprocessing
  FlowDriver = pysu2.CSinglezoneDriver(flow_filename, 1, comm);
  
  print("\n------------------------------ Begin Solver -----------------------------\n")
  sys.stdout.flush()
  comm.Barrier()

  Flow_Time  = FlowDriver.GetTime_Iter()
  Flow_nTime = FlowDriver.GetnTimeIter()

  for i in range(Flow_nTime):

    # Time iteration preprocessing
    FlowDriver.Preprocess(Flow_Time+i)
    FlowDriver.Run()
    FlowDriver.Postprocess()
    FlowDriver.Update()
    FlowDriver.Output(Flow_Time+i)
    stopCalc = FlowDriver.Monitor(Flow_Time+i)
    if stopCalc:
        break

# -------------------------------------------------------------------
#  Run Main Program
# -------------------------------------------------------------------

# this is only accessed if running from command prompt
if __name__ == '__main__':

    world_rank = MPI.COMM_WORLD.Get_rank()
    world_size = MPI.COMM_WORLD.Get_size()

    if world_rank < world_size//2:
        color = 1
    else:
        color = 2

    comm = MPI.COMM_WORLD.Split(color,world_rank)

    print('[Pre Barrier] My Rank is: ' + str(world_rank))
    sys.stdout.flush()

    comm1.Barrier() # Checking the communicator was correctly created

    print('[Post Barrier] My Rank is: ' + str(world_rank))
    sys.stdout.flush()

    if world_rank < world_size//2:
        main(comm)

[pcg]

That was added in version 7.1.1
Third feature from the top https://github.com/su2code/SU2/releases/tag/v7.1.1

[jbae]

Thank you. I was in one of the developer branches. The origin branch seems to work fine.