[petsc-dev] [GPU] src/ksp/ksp/examples/tutorials/ex9 fails with mpirun -np 2

Karl Rupp rupp at iue.tuwien.ac.at
Fri Mar 28 05:52:07 CDT 2014


Hi Pierre,

I could reproduce the problem, but I could also verify that the problem 
you ran into was due to a currently unsupported block-Jacobi 
preconditioner. That is, if you first comment the KSPSolve for the ksp2 
object in ex9, recompile ex9, and then run

$> mpiexec -np 2 ./ex9 -ksp_monitor -mat_type aijcusp -vec_type cusp 
-pc_type none

thinks should work out. This may also be applicable to your case: Give 
it a try with -pc_type none and let us whether the problem with 
VecSetValues remains. (The use of no preconditioner is certainly not 
great, but at least it may give you a first result)

Best regards,
Karli



On 03/26/2014 06:38 PM, Projet_TRIOU wrote:
> Hello all,
>
> My parallel code is really near to run using GPU device
> thanks to PETSc but I am struggling with the best way
> to fill the PETSc vectors in order in runs on CPU & GPU.
>
> I was using in the past, VecCreateMPIWithArray, to
> create vector but I had trouble with it on GPU.
>
> So I followed the example in the src/ksp/ksp/examples/tutorials/ex2.c
> and create now the vectors like this:
>
>    // Build x
>    ierr = VecCreate(PETSC_COMM_WORLD,&SecondMembrePetsc_); check(ierr);
>    ierr = VecSetSizes(SecondMembrePetsc_, nb_rows, nb_rows_tot);
> check(ierr);
>    ierr = VecSetFromOptions(SecondMembrePetsc_); check(ierr);
>    // Build b
>    ierr = VecDuplicate(SecondMembrePetsc_,&SolutionPetsc_);check(ierr);
>
> And fills it with VecSetValues function. It runs well on CPU and
> GPU but crashed only in parallel on GPU. It I use VecSet instead of
> VecSetValues, it didn't crash (but of course VecSet is not enough
> for me :-)
>
> I tried to find an example to reproduce for you the problem, and I
> think src/ksp/ksp/examples/tutorials/ex9 (it is usingVecSetValues,)
> is a good one.
>
> Or did I miss something (I also try VecPlaceArray/VecRestoreArray
> but without success on GPU) ?
>
> Thanks, and yes you are right,  "WARNING: Using GPUs effectively is
> difficult!" :-)
>
> Pierre
>
> sitre.intra.cea.fr:/work/triou/git/petsc-dev/Trio_U/lib/src/LIBPETSC/petsc/linux_opt/src/ksp/ksp/examples/tutorials
>  > ./ex9 -ksp_monitor
>    0 KSP Residual norm 6.612932697792e+00
>    1 KSP Residual norm 4.261830032389e-01
>    2 KSP Residual norm 2.121746090851e-02
>    3 KSP Residual norm 1.233779841608e-03
>    4 KSP Residual norm 1.265903168531e-05
>    0 KSP Residual norm 1.309416176382e-05
>    0 KSP Residual norm 1.404919664063e-05
>
> sitre.intra.cea.fr:/work/triou/git/petsc-dev/Trio_U/lib/src/LIBPETSC/petsc/linux_opt/src/ksp/ksp/examples/tutorials
>  > mpiexec -np 2 ./ex9 -ksp_monitor
>    0 KSP Residual norm 2.496821857304e+02
>    1 KSP Residual norm 4.522206074831e+01
>    2 KSP Residual norm 1.959482408314e+01
>    3 KSP Residual norm 7.002013703407e+00
>    4 KSP Residual norm 2.144105201713e+00
>    5 KSP Residual norm 1.780095080270e-01
>    6 KSP Residual norm 5.642702243268e-02
>    7 KSP Residual norm 6.439343992306e-03
>    8 KSP Residual norm 3.012756374415e-04
> Norm of error 0.000249108, Iterations 8
> Norm of error 0.000715584, Iterations 6
>    0 KSP Residual norm 3.422287562824e-04
> Norm of error 0.000249108, Iterations 0
> Norm of error 0.000192805, Iterations 7
>    0 KSP Residual norm 4.140588954098e-04
> Norm of error 0.000249108, Iterations 0
> Norm of error 0.000109507, Iterations 7
>
> sitre.intra.cea.fr:/work/triou/git/petsc-dev/Trio_U/lib/src/LIBPETSC/petsc/linux_opt/src/ksp/ksp/examples/tutorials
>  > ./ex9 -ksp_monitor -mat_type aijcusp -vec_type cusp
>    0 KSP Residual norm 6.612932697792e+00
>    1 KSP Residual norm 4.261830032389e-01
>    2 KSP Residual norm 2.121746090851e-02
>    3 KSP Residual norm 1.233779841608e-03
>    4 KSP Residual norm 1.265903168531e-05
>    0 KSP Residual norm 1.309416176403e-05
>    0 KSP Residual norm 1.404919664088e-05
>
> sitre.intra.cea.fr:/work/triou/git/petsc-dev/Trio_U/lib/src/LIBPETSC/petsc/linux_opt/src/ksp/ksp/examples/tutorials
>  > mpiexec -np 2 ./ex9 -ksp_monitor -mat_type aijcusp -vec_type cusp
> [0]PETSC ERROR:
> ------------------------------------------------------------------------
> [0]PETSC ERROR: Caught signal number 11 SEGV: Segmentation Violation,
> probably memory access out of range
> [0]PETSC ERROR: Try option -start_in_debugger or -on_error_attach_debugger
> [0]PETSC ERROR: or see
> http://www.mcs.anl.gov/petsc/documentation/faq.html#valgrind[0]PETSC
> ERROR: or try http://valgrind.org on GNU/linux and Apple Mac OS X to
> find memory corruption errors
> [0]PETSC ERROR: configure using --with-debugging=yes, recompile, link,
> and run
> [0]PETSC ERROR: to get more information on the crash.
> [0]PETSC ERROR: --------------------- Error Message
> --------------------------------------------------------------
> [0]PETSC ERROR: Signal received
> [0]PETSC ERROR: See
> http://http://www.mcs.anl.gov/petsc/documentation/faq.html for trouble
> shooting.
> [0]PETSC ERROR: Petsc Development GIT revision: v3.4.4-3713-g576f62e
> GIT Date: 2014-03-23 15:59:15 -0500
> [0]PETSC ERROR: ./ex9 on a linux_opt named sitre.intra.cea.fr by triou
> Wed Mar 26 18:32:34 2014
> [0]PETSC ERROR: Configure options
> --prefix=/work/triou/git/petsc-dev/Trio_U/lib/src/LIBPETSC/petsc/linux_opt
> --with-single-library --with-shared-libraries=0 --with-debugging=0
> --with-errorchecking=1 --COPTFLAGS="   -O3 -fPIC " --CXXOPTFLAGS=" -O3
> -fPIC " --FOPTFLAGS="  -O3 -fPIC " --with-fortran=yes --with-clean=1
> --download-scalapack=../scalapack-2.0.2.tgz
> --download-mumps=../MUMPS_4.10.0-p3.tar.gz --download-superlu_dist=yes
> --download-parmetis=../parmetis-4.0.2-p4.tar.gz
> --download-metis=../metis-5.0.2-p3.tar.gz
> --download-ptscotch=../ptscotch.tar.gz
> --download-hypre=../hypre-2.9.1a.tar.gz
> --with-valgrind-include=/work/triou/git/petsc-dev/Trio_U/exec/valgrind/include
> --with-blas-lapack-dir=/work/triou/git/petsc-dev/Trio_U/lib/src/LIBLAPACK --with-cuda=1
> --with-cuda-dir=/work/triou/git/petsc-dev/Trio_U/exec/cuda5.5
> --with-cusp=1
> --with-cusp-dir=/work/triou/git/petsc-dev/Trio_U/lib/src/LIBPETSC/cusplibrary-0.4.0
> --with-thrust=1 --with-cuda-arch=sm_21 --with-ssl=0
> --with-mpi-dir=/work/triou/git/petsc-dev/Trio_U/lib/src/LIBMPI/mpich
> --with-x=1
> [0]PETSC ERROR: #1 User provided function() line 0 in  unknown file
> [1]PETSC ERROR:
> ------------------------------------------------------------------------
> [1]PETSC ERROR: Caught signal number 11 SEGV: Segmentation Violation,
> probably memory access out of range
> [1]PETSC ERROR: Try option -start_in_debugger or -on_error_attach_debugger
> [1]PETSC ERROR: or see
> http://www.mcs.anl.gov/petsc/documentation/faq.html#valgrind[1]PETSC
> ERROR: or try http://valgrind.org on GNU/linux and Apple Mac OS X to
> find memory corruption errors
> [1]PETSC ERROR: configure using --with-debugging=yes, recompile, link,
> and run
> [1]PETSC ERROR: application called MPI_Abort(MPI_COMM_WORLD, 59) - process 0
> to get more information on the crash.
> [1]PETSC ERROR: --------------------- Error Message
> --------------------------------------------------------------
> [1]PETSC ERROR: Signal received
> [1]PETSC ERROR: See
> http://http://www.mcs.anl.gov/petsc/documentation/faq.html for trouble
> shooting.
> [1]PETSC ERROR: Petsc Development GIT revision: v3.4.4-3713-g576f62e
> GIT Date: 2014-03-23 15:59:15 -0500
> [1]PETSC ERROR: ./ex9 on a linux_opt named sitre.intra.cea.fr by triou
> Wed Mar 26 18:32:34 2014
> [1]PETSC ERROR: Configure options
> --prefix=/work/triou/git/petsc-dev/Trio_U/lib/src/LIBPETSC/petsc/linux_opt
> --with-single-library --with-shared-libraries=0 --with-debugging=0
> --with-errorchecking=1 --COPTFLAGS="   -O3 -fPIC " --CXXOPTFLAGS=" -O3
> -fPIC " --FOPTFLAGS="  -O3 -fPIC " --with-fortran=yes --with-clean=1
> --download-scalapack=../scalapack-2.0.2.tgz
> --download-mumps=../MUMPS_4.10.0-p3.tar.gz --download-superlu_dist=yes
> --download-parmetis=../parmetis-4.0.2-p4.tar.gz
> --download-metis=../metis-5.0.2-p3.tar.gz
> --download-ptscotch=../ptscotch.tar.gz
> --download-hypre=../hypre-2.9.1a.tar.gz
> --with-valgrind-include=/work/triou/git/petsc-dev/Trio_U/exec/valgrind/include
> --with-blas-lapack-dir=/work/triou/git/petsc-dev/Trio_U/lib/src/LIBLAPACK --with-cuda=1
> --with-cuda-dir=/work/triou/git/petsc-dev/Trio_U/exec/cuda5.5
> --with-cusp=1
> --with-cusp-dir=/work/triou/git/petsc-dev/Trio_U/lib/src/LIBPETSC/cusplibrary-0.4.0
> --with-thrust=1 --with-cuda-arch=sm_21 --with-ssl=0
> --with-mpi-dir=/work/triou/git/petsc-dev/Trio_U/lib/src/LIBMPI/mpich
> --with-x=1
> [1]PETSC ERROR: #1 User provided function() line 0 in  unknown file
> application called MPI_Abort(MPI_COMM_WORLD, 59) - process 1
>
>
>
> --
> *Trio_U support team*
> Marthe ROUX (01 69 08 00 02) Saclay
> Pierre LEDAC (04 38 78 91 49) Grenoble




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