I know a few national labs that run OMPI w/Fedora 9, but that isn't on Nehalem hardware and is using gcc 4.3.x.
However, I think the key issue really is the compiler. I have seen similar problems on multiple platforms and OS's whenever I use GCC 4.4.x - I -think- it has to do with the automatic vectorization in that compiler, but I can't swear to it. You can always install a personal copy of gcc for your own use on the system and see if that solves the problem. Just download a version like 4.3.x from the gnu site. I know 4.3.x doesn't have a problem, though again I haven't tried it on Nehalem. On May 6, 2010, at 12:10 PM, Gus Correa wrote: > Hi Jeff > > Thank you for your testimony. > > So now I have two important data points (you and Douglas Guptill) > to support the argument here that installing Fedora > on machines meant to do scientific and parallel computation > is to ask for trouble. > > I use CentOS in our cluster, but this is a standalone machine > I don't have control of. > > Anybody out there using Open MPI + Fedora Core + Nehalem ? > Happy? > > Regards, > Gus Correa > > Jeff Squyres wrote: >> On May 6, 2010, at 1:11 PM, Gus Correa wrote: >>> Just for the record, I am using: >>> Open MPI 1.4.2 (released 2 days ago), gcc 4.4.3 (g++, gfortran). >>> All on Fedora Core 12, kernel 2.6.32.11-99.fc12.x86_64 #1 SMP. >> Someone asked earlier in this thread -- I've used RHEL4.4 and RHEL5.4 on my >> Nehalem EP boxen. I used the default gcc on those RHELs for compiling >> everything (OMPI + apps). I don't remember what it was on RHEL 4.4, but on >> RHEL 5.4, it's GCC 4.1.2. >>> You and Jeff reported that your >>> Nehalems get along with Open MPI. >>> I would guess other people have functional Open MPI + Nehalem systems. >>> All I can think of is that some mess with the OS/gcc is causing >>> the trouble here. >> I don't have much experience with kernels outside > of the RHEL kernels, > so I don't know if 2.6.32 is problematic or not. :-( > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users
