Randy, Please take a look at https://gitlab.com/petsc/petsc/-/merge_requests/4543/ <https://gitlab.com/petsc/petsc/-/merge_requests/4543/> and try its branch. It has more features and may provide more of what you need.
Barry > On May 23, 2022, at 1:59 PM, Randall Mackie <rlmackie...@gmail.com> wrote: > > Dear PETSc team: > > I am trying to use Strumpack in ILU mode, which is suppose to activate it’s > low rank approximation as described on the man page: > > https://petsc.org/release/docs/manualpages/Mat/MATSOLVERSSTRUMPACK.html > <https://petsc.org/release/docs/manualpages/Mat/MATSOLVERSSTRUMPACK.html> > > and in this exchange a few years ago: > > https://lists.mcs.anl.gov/pipermail/petsc-users/2017-October/033560.html > <https://lists.mcs.anl.gov/pipermail/petsc-users/2017-October/033560.html> > > > However, regardless of whether I specify ILU or LU, the behavior is the same, > and the solution is in 1 step, meaning (to me) it’s doing the LU direct solve. > Furthermore, when I set verbose mode, it doesn’t seem to be activating low > rank mode (that is, there are HSS or BLR frontal matrices created). > > > I’m running this example: > > https://petsc.org/release/src/ksp/ksp/tutorials/ex2.c.html > <https://petsc.org/release/src/ksp/ksp/tutorials/ex2.c.html> > > using options: > > mpiexec -n 4 ./ex2 -pc_type ilu -pc_factor_mat_solver_package strumpack > > I’m likely doing something wrong, but I can’t figure out what, and would > appreciate advice on how to use the strumpack ILU mode. > > Thanks, Randy M. > >