Prentice, could you please run lstopo --of=xml and post the output ?
a simple workaround could be to bind each task to two consecutive cores (assuming two consecutive cores share the same FPU, will know for sure after i check the topology) that can be achieved with mpirun --map-by socket:span,PE=2 ... if two cores sharing the same FPU also happen to share the same L2 cache, an other work around would be to bind to a L2 cache. Cheers, Gilles On Wed, Aug 30, 2017 at 6:00 AM, Prentice Bisbal <pbis...@pppl.gov> wrote: > I'd like to follow up to my own e-mail... > > After playing around with the --bind-to options, it seems there is no way to > do this with AMD CMT processors, since they are actual physical cores, and > not hardware threads that appear as "logical cores" as with Intel processors > with hyperthreading. Which, in hindsight, makes perfect sense. > > In the BIOS, you can turn reduce the number of cores to match the number of > FPUs. On the SuperMicro systems I was testing on, the options is called > "Downcore" (or somethiing like that) and I set to a value of "compute unit" > > Prentice > > On 08/24/2017 03:11 PM, Prentice Bisbal wrote: >> >> OpenMPI Users, >> >> I am using AMD processocers with CMT, where two cores constitute a module, >> and there is only one FPU per module, so each pair of cores has to share a >> single FPU. I want to use only one core per module so there is no >> contention between cores in the same module for the single FPU. Is this >> possible from the command-line using mpirun with the correct binding >> specifications? If so, how would I do this? >> >> I am using OpenMPI 1.10.3. I read the man page regarding the bind-to-core >> options, and I'm not sure that will do exactly what I want, so I figured I'd >> ask the experts here. >> > > _______________________________________________ > 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
