Brice, I'm a developer of Fujitsu MPI for K computer and Fujitsu PRIMEHPC FX10/FX100 (SPARC-based CPU).
Though I'm not familiar with the hwloc code and didn't know the issue reported by Gilles, I also would be able to help you to fix the issue. Takahiro Kawashima, MPI development team, Fujitsu > Thanks Brice, > > bottom line, even if hwloc is not fully ported, it should build and ompi > should get something usable. > in this case, i have no objection removing the --without-hwloc configure > option. > > you can contact me off-list regarding the FX10 specific issue > > Cheers, > > Gilles > > On 9/4/2015 2:31 PM, Brice Goglin wrote: > > Le 04/09/2015 00:36, Gilles Gouaillardet a écrit : > >> Ralph, > >> > >> just to be clear, your proposal is to abort if openmpi is configured > >> with --without-hwloc, right ? > >> ( the --with-hwloc option is not removed because we want to keep the > >> option of using an external hwloc library ) > >> > >> if I understand correctly, Paul's point is that if openmpi is ported > >> to a new architecture for which hwloc has not been ported yet > >> (embedded hwloc or external hwloc), then the very first step is to > >> port hwloc before ompi can be built. > >> > >> did I get it right Paul ? > >> > >> Brice, what would happen in such a case ? > >> embedded hwloc cannot be built ? > >> hwloc returns little or no information ? > > > > If it's a new operating system and it supports at least things like > > sysconf, you will get a Machine object with one PUs per logical processor. > > > > If it's a new platform running Linux, they are supposed to tell Linux > > at least package/core/thread information. That's what we have for ARM > > for instance. > > > > Missing topology detection can be worked around easily (with XML and > > synthetic description, what we did for BlueGene/Q before adding manual > > support for that specific processor). Binding support can't. > > And once you get binding, you get x86-topology even if the operating > > system isn't supported (using cpuid). > > > >> for example, on Fujitsu FX10 node (single socket, 16 cores), hwloc > >> reports 16 sockets with one core each and no cache. though this is > >> not correct, that can be seen as equivalent to the real config by > >> ompi, so this is not really an issue for ompi. > > > > Can you help fixing this? > > > > The issue is indeed with supercomputers with uncommon architectures > > like this one.
