Just to confirm that we were seeing illegal instruction crashes linking against:
-lesslbgsmp but -lesslbg appears to be fine. There may be an environment variable or compile option to set for the SMP-friendly ESSL to work properly. I don't have any clue. A On Tue, Sep 14, 2010 at 11:56 PM, Aron Ahmadia <aron.ahmadia at kaust.edu.sa>wrote: > Jed, I went back and recompiled a PETSc that didn't make use of the KTH > LAPACK/CBLAS build, so the problem definitely lies within the daxpy calls to > the essl library, and not PETSc's interpretation of the interface. At this > point the potential culprits are misaligned memory or some bad > initialization to the multithreaded ESSL. In the past I've used the > smp-friendly ESSL without any trouble, so I am surprised that this code is > throwing illegal instruction signals. I am rebuilding PETSc now to point to > the single-threaded BG ESSL. If this fails as well I will get some help > from the IBM guys to shed some light on what's going on. > > --Aron > > > On Mon, Sep 13, 2010 at 2:59 PM, Aron Ahmadia <aron.ahmadia at > kaust.edu.sa>wrote: > >> ESSL contains a BLAS, but you can get a nice standard LAPACK/CBLAS on >> BlueGene by following these instructions: >> http://www.pdc.kth.se/resources/computers/bluegene/LAPACK-CBLAS/LAPACK-CBLAS-build >> >> A >> >> >> On Mon, Sep 13, 2010 at 2:55 PM, Barry Smith <bsmith at mcs.anl.gov> wrote: >> >>> >>> On Sep 13, 2010, at 1:56 PM, Jed Brown wrote: >>> >>> > On Mon, 13 Sep 2010 13:42:05 -0500, Barry Smith <bsmith at mcs.anl.gov> >>> wrote: >>> >> My point is not only do they get a slower GEEV but they get a slower >>> >> everything in LAPACK. [...] Why not just use LAPACK? >>> > >>> > Yup, I get your point. But Lapack usually needs a BLAS, and the >>> > original (flawed) idea was that a fast BLAS would produce a competitive >>> > Lapack. >>> > >>> What, Jack made a mistake? Never. >>> >>> Does ESSL itself contain "the BLAS" or is there also a libblas type >>> thingy on the IBM you could link against? >>> >>> None of this really matters because you are still stuck writing the >>> configure test for geev. >>> >>> Barry >>> >>> >>> > Jed >>> >>> >> > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20100915/8e1d5d09/attachment.html>
