Hi everyone, on my 2 cores/4 threads development platform I want to start programs via mpirun with over-subscription enabled by default. I have some external packages which have tests that use more than 2 processes. They all fail because Open MPI refuses them to run due to over-subscription. I know that I can enable over-subscription with mpirun --oversubscribe and that works well, but that would require to modify the packages' autotools files or the generated Makefiles with I found hardly convenient.
I also tried two of the RMAPS MCA parameters: - rmaps_base_no_oversubscribe - rmaps_base_oversubscribe (btw, are they redundant? Having two of them and one is the negation of the other is quite confusing. The description in ompi_info reads quite similar for the two.) $ mpirun --mca rmaps_base_no_oversubscribe 0 --mca rmaps_base_oversubscribe 1 -n 4 hostname -------------------------------------------------------------------------- There are not enough slots available in the system to satisfy the 4 slots that were requested by the application: hostname Either request fewer slots for your application, or make more slots available for use. -------------------------------------------------------------------------- Setting the environment variables (OMPI_MCA_rmaps_...) did not help either. The same goes or the FAQ [1]: $ cat > my-hostfile localhost $ mpirun -np 4 --hostfile my-hostfile hostname -------------------------------------------------------------------------- There are not enough slots available in the system to satisfy the 4 slots... My Open MPI installation is a private build of version 4.0.0, configured with nothing more than ./configure --prefix=/some/where --enable-mpi-fortran How can I allow over-subscription by default? I am aware about performance implications, but it's only used for testing and development. I am not using a resource manager on that machine. Thanks in advance Regards, Steffen [1] https://www.open-mpi.org/faq/?category=running#oversubscribing _______________________________________________ users mailing list users@lists.open-mpi.org https://lists.open-mpi.org/mailman/listinfo/users
