Gilles, You have the nature of my question correct. To restate:
Imagine somebody is developing an experimental platform (such as a research OS) and they want an MPI for it. Additionally assume that hwloc (the embedded one or otherwise) doesn't build at all for this platform. It is my understanding (please correct if I've got it wrong) that currently they can configure using --without-hwloc. My concern is that if --without-hwloc is dropped then they cannot build Open MPI at all without first porting hwloc. -Paul On Thu, Sep 3, 2015 at 3:36 PM, Gilles Gouaillardet < [email protected]> wrote: > 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 ? > > 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. > > Cheers, > > Gilles > > On Friday, September 4, 2015, Ralph Castain <[email protected]> wrote: > >> No - hwloc is embedded in OMPI anyway. >> >> On Sep 3, 2015, at 11:09 AM, Paul Hargrove <[email protected]> wrote: >> >> >> On Thu, Sep 3, 2015 at 8:03 AM, Ralph Castain <[email protected]> wrote: >> >>> Does anyone know of a reason why we shouldn’t do this? >>> >> >> >> Would doing this mean that a port to a new system would require that one >> first perform a full hwloc port? >> >> -Paul >> >> -- >> Paul H. Hargrove [email protected] >> Computer Languages & Systems Software (CLaSS) Group >> Computer Science Department Tel: +1-510-495-2352 >> Lawrence Berkeley National Laboratory Fax: +1-510-486-6900 >> _______________________________________________ >> devel mailing list >> [email protected] >> Subscription: http://www.open-mpi.org/mailman/listinfo.cgi/devel >> Link to this post: >> http://www.open-mpi.org/community/lists/devel/2015/09/17942.php >> >> >> > _______________________________________________ > devel mailing list > [email protected] > Subscription: http://www.open-mpi.org/mailman/listinfo.cgi/devel > Link to this post: > http://www.open-mpi.org/community/lists/devel/2015/09/17952.php > -- Paul H. Hargrove [email protected] Computer Languages & Systems Software (CLaSS) Group Computer Science Department Tel: +1-510-495-2352 Lawrence Berkeley National Laboratory Fax: +1-510-486-6900
