On Tue, Sep 6, 2011 at 11:25 AM, Randall Mackie <rlmackie862 at gmail.com>wrote:
> > On Sep 6, 2011, at 9:16 AM, Matthew Knepley wrote: > > On Tue, Sep 6, 2011 at 11:12 AM, Randall Mackie <rlmackie862 at > gmail.com>wrote: > >> >> On Sep 6, 2011, at 9:08 AM, Barry Smith wrote: >> >> > >> > >> > On Sep 6, 2011, at 10:59 AM, Daniel Lowell wrote: >> > >> >> On this page: http://www.mcs.anl.gov/petsc/petsc-as/features/gpus.html >> >> >> >> It states: "All of the Krylov methods except KSPIBCGS run on the GPU." >> >> I actually could only find ksp/pc/bicgstabcusp for any ksp >> implementation on the GPU. >> > >> > Daniel, >> > >> > All the vector operations and the matrix-vector product used by the >> Krylov methods implemented in PETSc (except KSPIBCGS) run on the GPU without >> copying up or down vector or matrix values, in the same way as >> ksp/pc/bicgstabcusp does, hence we say they run on the GPU. In fact, in our >> tests our BiGCStab runs just as fast as the Nvidia CUSP code >> ksp/pc/bicgstabcusp. >> > >> > In other words, higher level algorithms such as Krylov methods and >> Newton methods do not need to be "written for the GPU", so long as the >> kernel operations run on the GPU. >> > >> > >> > >> > Barry >> >> Barry, >> >> But is this still only for real data types? Last time I checked, earlier >> this year, complex valued data were not >> supported under PETSc, even though complex data types are supported in >> CUSP. >> > > I have not tried, but I do not understand why it would not work. We just > use PetscScalar. Can you send > the problem you found? > > Matt > > > > Matt, > > Here is the message that I received earlier this year, but I never did have > time to follow up on it then: > Ah, so I would characterize this as "CUSP does not work with std::complex", which is a big problem. Matt > > *From: *Barry Smith <bsmith at mcs.anl.gov> > *Date: *May 24, 2011 5:04:51 AM PDT > *To: *petsc-maint at mcs.anl.gov, Victor Minden <victorminden at gmail.com> > *Cc: *Randall Mackie <rlmackie862 at gmail.com> > *Subject: **Re: [petsc-maint #71751] error during compile* > > > Victor, > > Thanks for the info. I've forgotten about the blas. > > Randall, > > Looks like it is not so trivial as I had made it out to be. Perhaps if > you ask on petsc-dev at mcs.anl.gov there may be people who want this also > and are willing to share the work? > > Barry > > On May 23, 2011, at 6:06 PM, Victor Minden wrote: > > Barry, > > > Currently there should be two things going on--one is that some of the > > CUBLAS routines used for basic vector operations (which we've been moving > > away from) have 4 different forms depending on single/double and > > real/complex--currently those that we still use are hard-coded as real and > > #ifdeffed to be single/double, and I haven't looked in depth but I think > > those are the errors that Randy sent. > > > Those should be pretty quick to change, but they won't make complex work, > > because once you get past veccusp.cu there are a bunch more errors in the > > cusp matrix routines which work with complex if you use the relatively new > > (Oct? Dec?) cusp complex type that they've added to the cusp library. So, > > we need to make the GPU routines work with the standard complex type or we > > need to convert all the GPU code to use the cusp type. I don't know how > > much work this is. > > > As it stands, I'm just starting my internship this week so I probably won't > > be able to look at this in-depth until the weekend, just FYI. > > > Cheers, > > > Victor > > --- > > Victor L. Minden > > > Tufts University > > School of Engineering > > Class of 2012 > > > > > > > >> Randy >> >> >> > >> >> >> >> CUSP does have everything mentioned in the above PETSc link: >> >> >> http://code.google.com/p/cusp-library/wiki/QuickStartGuide#Iterative_Solvers >> >> >> >> However I don't see where any of it is implemented in the latest Dev >> release, Krylov solvers or preconditioners. >> >> >> >> Can anyone clear this up for me? >> >> >> >> Thanks, >> >> >> >> Daniel Lowell >> > >> >> > > > -- > What most experimenters take for granted before they begin their > experiments is infinitely more interesting than any results to which their > experiments lead. > -- Norbert Wiener > > > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20110906/e4d4b895/attachment.html>