[petsc-users] KSPSetOperators/sub-preconditioner type

[Paul T. Bauman]

Greetings,

This question is somewhat related to this thread:
http://lists.mcs.anl.gov/pipermail/petsc-users/2011-August/009583.html but
instead of resurrecting that thread, I decided to start a new one.

Summary: In the libMesh wrapper of PETSc's KSP, a call is made to
KSPSetOperators; I gather this is in order to allow reusing the same
preconditioner, if desired. However, I've noticed that when I use the
following options, the sub-preconditioner type gets reset:

-pc_type bjacobi -sub_pc_type ilu -sub_pc_factor_mat_solver_package superlu

In particular, the first linear solve uses what I asked for, but in all
following linear solves, the petsc ilu solver is used instead of superlu.
If I remove the KSPSetOperators call, everything is peachy.

My question: Does a call need to be made to PCSetFromOptions (or something
similar...) to keep the superlu ilu solver around or would that wipe out
the KSPSetOperators effect? Is this a PETSc bug? Other?

This is with petsc-3.3-p1.

Thanks for your time.

Best,

Paul
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