Note that the lama mapper described in those slides may not work as it hasn't been maintained in a while. However, you can use the map-by and bind-to options to do the same things.
If you want to disable binding, you can do so by adding "--bind-to none" to the cmd line, or via the MCA param "hwloc_base_binding_policy=none" If you want to bind your process to multiple cores (say one per thread), then you can use "--map-by core:pe=N". Many hybrid users prefer to bind to a socket, with one process for each socket - that can be done with "--map-by socket --bind-to socket". This keeps all the threads in the same NUMA domain. If you aren't sure that each socket is its own NUMA domain, you can alternatively "--map-by numa --bind-to numa" - that'll keep you in your own NUMA domain regardless of whether that's at the socket level or elsewhere. I'm working on adding a full description of the mapping/binding system to our web site. HTH Ralph On May 23, 2014, at 6:22 AM, Brock Palen <bro...@umich.edu> wrote: > Albert, > > Actually doing affinity correctly for hybrid got easier in OpenMPI 1.7 and > newer, In the past you had to make a lot of assumptions, stride by node etc, > > Now you can define a layout: > > http://blogs.cisco.com/performance/eurompi13-cisco-slides-open-mpi-process-affinity-user-interface/ > > Brock Palen > www.umich.edu/~brockp > CAEN Advanced Computing > XSEDE Campus Champion > bro...@umich.edu > (734)936-1985 > > > > On May 23, 2014, at 9:19 AM, Albert Solernou <albert.soler...@oerc.ox.ac.uk> > wrote: > >> Hi, >> after compiling and installing OpenMPI 1.8.1, I find that OpenMPI is pinning >> processes onto cores. Although this may be >> desirable on some cases, it is a complete disaster when runnning hybrid >> OpenMP-MPI applications. Therefore, I want to disable this behaviour, but >> don't know how. >> >> I configured OpenMPI with: >> ./configure \ >> --prefix=$OPENMPI_HOME \ >> --with-psm \ >> --with-tm=/system/software/arcus/lib/PBS/11.3.0.121723 \ >> --enable-mpirun-prefix-by-default \ >> --enable-mpi-thread-multiple >> >> and: >> ompi_info | grep paffinity >> does not report anything. However, >> mpirun -np 2 --report-bindings ./wrk >> reports bindings: >> [login3:04574] MCW rank 1 bound to socket 0[core 1[hwt 0-1]]: >> [../BB/../../../../../..][../../../../../../../..] >> [login3:04574] MCW rank 0 bound to socket 0[core 0[hwt 0-1]]: >> [BB/../../../../../../..][../../../../../../../..] >> but they cannot be disabled as: >> mpirun -np 2 --bind-to-none ./wrk >> returns: >> mpirun: Error: unknown option "--bind-to-none" >> >> Any idea on what went wrong? >> >> Best, >> Albert >> >> -- >> --------------------------------- >> Dr. Albert Solernou >> Research Associate >> Oxford Supercomputing Centre, >> University of Oxford >> Tel: +44 (0)1865 610631 >> --------------------------------- >> _______________________________________________ >> users mailing list >> us...@open-mpi.org >> http://www.open-mpi.org/mailman/listinfo.cgi/users > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users
