-da_grid_x 5
-da_grid_y 5
-dmmg_nlevels 3

-snes_atol 1.e-12

-ksp_type gmres
-ksp_atol 1.e-14
-ksp_left_pc

-mg_coarse_pc_type lu
-mg_coarse_pc_lu_damping
-mg_levels_pc_type sor
-mg_levels_pc_sor_local_symmetric
-mg_levels_ksp_type richardson