Hypre

[Matthew Knepley]

On Thu, Apr 17, 2008 at 5:23 AM,  <tribur at vision.ee.ethz.ch> wrote:
> Dear Petsc experts,
>
>  Another, more basic problem when using Hypre:
>
>  When I try
>
>  ex2_hdf5 -f data/sphereInBlockFiner_a_cd3t.h5 -pc_type hypre -pc_hypre_type
> pilut -log_summary
>
>  where sphereInBlock_a_cd3t.h5 contains a 102464 x 102464 matrix,
>  the program seems to hang (it stops with the error "=>> PBS: job killed:
> walltime 384 exceeded limit 360").
>  Adding the option -ksp_max_it 1 to be sure that it is not iterating until
> 10000000000000 doesn't change anything. The same happens also if I use
> -pc_hypre_type boomeramg.

If you really think it is hanging, I would attach gdb and get a stack
trace. You can
either run with -start_in_debugger, or attach gdb to the running process with
gdb <process id>. It is conceivable to me that pilut just takes a
really long time
to factor the matrix. For boomeramg this is less likely, but still believeable.

   Matt

>  It is neither the problem of my program nor of the matrix, because
>
>  ex2_hdf5 -f data/sphereInBlockFiner_a_cd3t.h5 -pc_type jacobi -log_summary
> -ksp_rtol 0.0000000001
>
>  takes only 5s and gives me the correct solution.
>
>  What do I do wrong?
>
>  Looking forward to your answer,
>  Kathrin
>
>



-- 
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