Normally, mpi_run starts via ssh on remote node orted process, and orted start mpi_program via fork+exec. orted and mpi_program communicate via: - environment variables (ok, that's on-time setup only, but still) - pipes (only one, right? - it is close-on-exec by child). - file descriptors, mpi_program stdin/out/err are redirected in orted between fork and exec. - socket (only one?), mpi_program connects to OMPI_MCA_orte_local_daemon_uri - session dir (OMPI_FILE_LOCATION) (did I miss anything - or, how much?)
How is session dir used? I saw check for aborted file (so that orted can figure out if child died?). Is there any other use of that dir? Can I just ignore it, if I try to run orted on host, and mpi_program in container/virtual machine?