Hi Jeff, as written in my original post, I'm using a custom build of 4.0.0 which was configured with nothing more than a --prefix and --enable-mpi-fortran. I checked for updates and it appears that there was an issue until 4.0.1 with oversubscription. The changelog states
> - Fix a problem with the ORTE rmaps_base_oversubscribe MCA paramater. Using --mca rmaps_base_oversubscribe 1 on the command line works with the 4.0.1 version. I added an entry in the openmpi-mca-params.conf file and I can now use over-subscribing calls of mpirun without any additional arguments aside from the number of processes. Regards, Steffen On 16/04/2019 19.48, Jeff Squyres (jsquyres) via users wrote: > Steffen -- > > What version of Open MPI are you using? > > >> On Apr 16, 2019, at 9:21 AM, Steffen Christgau <christ...@cs.uni-potsdam.de> >> wrote: >> >> Hi Tim, >> >> it helps, up to four processes. But it has two drawbacks. 1) Using more >> cores/threads than the machine provides (so the actual >> over-subscription) is still not possible. 2) it still requires an >> additional command line argument. >> >> What I'd like to see is that a call of mpirun with an arbitrary number >> of processes that just works without any other command line options. >> However, an environment variable would be acceptable. >> >> MPICH's (v3.3) mpirun of a plain installation with no further configure >> options (I think it uses the Hydra PM) just does what I want, but MPICH >> is not always an option ;-) >> >> Regards, Steffen >> >> On 16/04/2019 14.56, Tim Jim wrote: >>> Hi Steffen, >>> >>> I'm not sure if this will help you (I'm by far no expert) but the >>> mailing group pointed by to using: >>> mpirun --use-hwthread-cpus >>> >>> to solve something similar. >>> >>> Kind regards, >>> Tim >>> >>> >>> On Tue, 16 Apr 2019 at 19:01, Steffen Christgau >>> <christ...@cs.uni-potsdam.de <mailto:christ...@cs.uni-potsdam.de>> wrote: >>> >>> 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 <mailto:users@lists.open-mpi.org> >>> https://lists.open-mpi.org/mailman/listinfo/users >>> >>> >>> >>> -- >>> >>> >>> >>> *Timothy Jim >>> */PhD Researcher in Aerospace/ >>> >>> Creative Flow Research Division, >>> Institute of Fluid Science, Tohoku University >>> >>> www.linkedin.com/in/timjim/ <http://www.linkedin.com/in/timjim/> >>> >>> >>> _______________________________________________ >>> users mailing list >>> users@lists.open-mpi.org >>> https://lists.open-mpi.org/mailman/listinfo/users >>> >> _______________________________________________ >> users mailing list >> users@lists.open-mpi.org >> https://lists.open-mpi.org/mailman/listinfo/users > > _______________________________________________ users mailing list users@lists.open-mpi.org https://lists.open-mpi.org/mailman/listinfo/users
