Okay, I can't promise when I'll get to it, but I'll try to have it in time for OMPI v5.
On Jan 29, 2021, at 1:30 AM, Luis Cebamanos via users <users@lists.open-mpi.org <mailto:users@lists.open-mpi.org> > wrote: Hi Ralph, It would be great to have it for load balancing issues. Ideally one could do something like --bind-to:N where N is the block size, 4 in this case. mpirun -np 40 --map-by ppr:40:node --bind-to core:4 I think it would be interesting to have it. Of course, I can always use srun but not all system run Slurm. Of course, you could fake it out even today by breaking it into multiple app-contexts on the cmd line. Something like this (again, shortening it to just two nodes): mpirun --map-by node --rank-by slot --bind-to core --np 8 myapp : --np 8 myapp : --np 8 myapp : --np 8 myapp : --np 8 myapp It is a valid options, tedious for large number of nodes though. Thanks!
