PCOPENMP

Runs a preconditioner for a single process matrix across several MPI processes

    This will usually be run with -pc_type openmp -ksp_type gmres -openmp_pc_type ksp then

    solver options are set with -openmp_ksp_ksp_... and -openmp_ksp_pc_... for example

    -openmp_ksp_ksp_type cg would use cg as the Krylov method or -openmp_ksp_ksp_monitor or

    -openmp_ksp_pc_type hypre -openmp_ksp_pc_hypre_type boomeramg

Always run with -ksp_view (or -snes_view) to see what solver is actually being used.

Currently the solver options INSIDE the OpenMP preconditioner can ONLY be set via the options database.

See PetscOpenMPMerge() and PetscOpenMPSpawn() for two ways to start up MPI for use with this preconditioner