Does this work for you? -pc_hypre_boomeramg_grid_sweeps_all 2 The comment in our code says SSOR is the default but it looks like it is really "hSGS" I thought it was an L1 Jacobi, but you would want to ask Hypre about this. Mark On Fri, Jan 5, 2024 at 10:21 AM Barry Smith <[email protected]> wrote:
Yes, the handling of BoomerAMG options starts at line 365. If we don't support what you want but hypre has a function call that allows one to set the values then the option could easily be added to the PETSc options database here either by you (with a merge request) or us. So I would say check the hypre docs.
Just let us know what BoomerAMG function is missing from the code.
Barry
On Jan 5, 2024, at 7:52 AM, Khurana, Parv <[email protected]> wrote:
Hello PETSc users community,
Happy new year! Thank you for the community support as always.
I am using BoomerAMG for my research, and it is interfaced to my software via PETSc. I can only use options database keys as of now to tweak the settings I want for the AMG solve.
I want to control the number of smoothener iterations at pre/post step for a given AMG cycle. I am looking for an options database key which helps me control this. I am not sure whether this is possible directly via the keys (Line 365: https://www.mcs.anl.gov/petsc/petsc-3.5.4/src/ksp/pc/impls/hypre/hypre.c.htm...). My comprehension of the current setup is that I have 1 smoothener iteration at every coarsening step. My aim is to do two pre and 2 post smoothening steps using the SSOR smoothener.
BoomerAMG SOLVER PARAMETERS:
Maximum number of cycles: 1 Stopping Tolerance: 0.000000e+00 Cycle type (1 = V, 2 = W, etc.): 1
Relaxation Parameters: Visiting Grid: down up coarse Number of sweeps: 1 1 1 Type 0=Jac, 3=hGS, 6=hSGS, 9=GE: 6 6 9 Point types, partial sweeps (1=C, -1=F): Pre-CG relaxation (down): 1 -1 Post-CG relaxation (up): -1 1 Coarsest grid: 0
PETSC settings I am using currently:
-ksp_type preonly -pc_type hypre -pc_hypre_type boomeramg -pc_hypre_boomeramg_coarsen_type hmis -pc_hypre_boomeramg_relax_type_all symmetric-sor/jacobi -pc_hypre_boomeramg_strong_threshold 0.7 -pc_hypre_boomeramg_interp_type ext+i -pc_hypre_boomeramg_P_max 2 -pc_hypre_boomeramg_truncfactor 0.3
Thanks and Best Parv Khurana