[petsc-users] Question about Set-up of Full MG and its Output

[frank]

Dear all,

I am trying to use full MG to solve a 2D Poisson equation.

I want to set full MG as the solver and SOR as the smoother. Is the 
following setup the proper way to do it?
  -ksp_type                    richardson
  -pc_type                      mg
  -pc_mg_type               full
  -mg_levels_ksp_type   richardson
  -mg_levels_pc_type    sor

The ksp_view shows the levels from the coarsest mesh to finest mesh in a 
linear order.
I was expecting sth like:  coarsest -> level1 -> coarsest -> level1 -> 
level2 -> level1 -> coarsest -> ...
Is there a way to show exactly how the full MG proceeds?

Also in the above example, I want to know what interpolation or 
prolongation method is used from level1 to level2.
Can I get that info by adding some options? (not using PCMGGetInterpolation)

I attached the ksp_view info and my petsc options file.
Thank you.

Frank
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-ksp_type        richardson
-ksp_norm_type   unpreconditioned
-ksp_rtol        1e-7
-options_left
-ksp_initial_guess_nonzero  yes
-ksp_converged_reason 
-ksp_view
-pc_type mg
-pc_mg_type full
-pc_mg_galerkin
-pc_mg_levels 6
-mg_levels_ksp_type richardson
-mg_levels_pc_type sor
-mg_levels_ksp_max_it 1
-mg_coarse_ksp_type preonly
-mg_coarse_pc_type lu
-mg_coarse_pc_factor_mat_solver_package superlu_dist