# options for PETSC using MPI
# To use his file, set environment variable PETSC_OPTIONS to
#       '-options_file  /path/to/this/file'

# Currently using GMRES Krylov space method as the main solver
# and algebraic multigrid as the preconditioner

# For more about the options, see
#    https://petsc.org/release/manualpages/KSP/KSPSetFromOptions
#    https://petsc.org/release/manualpages/PC/PCSetFromOptions/

# set min numbers of matrix rows per MPI rank  (default is 10000)
-pc_mpi_minimum_count_per_rank 5000

# convergence criterion for linear solver (larger than PETSc default):
-mpi_ksp_rtol 1.e-9

# linear solver:
-mpi_linear_solver_server
-ksp_type preonly
-mpi_ksp_type gmres
-mpi_ksp_max_it 200
-mpi_ksp_reuse_preconditioner

# preconditioner:
-pc_type mpi
-mpi_pc_type gamg
-mpi_pc_gamg_symmetrize_graph true
-mpi_pc_gamg_sym_graph true
-mpi_linear_solver_server_view

# debug options:
#-fp_trap off
#-log_view
#-start_in_debugger -debugger_rank 0
#-mpi_ksp_view_mat binary
#-mpi_ksp_view_rhs binary
#-mpi_ksp_monitor_true_residual
#-mpi_ksp_monitor
#-info

# test if any options are not used:
#-options_left