Mpi4py and subprocess.Popen ()

Question

I am trying to write a python script using mpi4py which launches a bunch of executables using subprocess.Popen () and then processes them after that, so I will need to know when the executables started.

I notice that mpi4py does not like subprocess.Popen () when I run it on a computer cluster. I tried using mpi4py Spawn (), but it does not tell me when the executable finished working.

Any ideas on how I should run executables. I will use thousands of these files on multiple nodes.