Nadia, Interesting. I haven't tried pushing this to levels above 8 on a particular machine. Do you think that the cpuset / paffinity / hwloc only applies at the machine level, at which time you need to employ a graph with carto?
Regards, Ken -----Original Message----- From: devel-boun...@open-mpi.org [mailto:devel-boun...@open-mpi.org] On Behalf Of nadia.derbey Sent: Monday, August 29, 2011 5:45 AM To: Open MPI Developers Subject: [OMPI devel] known limitation or bug in hwloc? Hi list, I'm hitting a limitation with paffinity/hwloc with cpu numbers >= 64. In opal/mca/paffinity/hwloc/paffinity_hwloc_module.c, module_set() is the routine that sets the calling process affinity to the mask given as parameter. Note that "mask" is a opal_paffinity_base_cpu_set_t (so we allow the cpus to be potentially numbered up to OPAL_PAFFINITY_BITMASK_CPU_MAX - 1). The problem with module_set() is that is loops over OPAL_PAFFINITY_BITMASK_T_NUM_BITS bits to check if these bits are set in the mask: for (i = 0; ((unsigned int) i) < OPAL_PAFFINITY_BITMASK_T_NUM_BITS; ++i) { if (OPAL_PAFFINITY_CPU_ISSET(i, mask)) { hwloc_bitmap_set(set, i); } } Given "mask"'s type, I think module_set() should instead loop over OPAL_PAFFINITY_BITMASK_CPU_MAX bits. Note that module_set() uses a type for its internal mask that is coherent with OPAL_PAFFINITY_BITMASK_T_NUM_BITS (hwloc_bitmap_t). So I'm wondering whether this is a known limitation I've never heard of or an actual bug? Regards, Nadia _______________________________________________ devel mailing list de...@open-mpi.org http://www.open-mpi.org/mailman/listinfo.cgi/devel ----- No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1392 / Virus Database: 1520/3864 - Release Date: 08/28/11
