Use -pc_type cholesky -pc_factor_mat_solver_type cholmod to use this direct solver
Consult CHOLMOD documentation for more information about the Common parameters which correspond to the options database keys below.
| -mat_cholmod_dbound <0> | - Minimum absolute value of diagonal entries of D (None) | |
| -mat_cholmod_grow0 <1.2> | - Global growth ratio when factors are modified (None) | |
| -mat_cholmod_grow1 <1.2> | - Column growth ratio when factors are modified (None) | |
| -mat_cholmod_grow2 <5> | - Affine column growth constant when factors are modified (None) | |
| -mat_cholmod_maxrank <8> | - Max rank of update, larger values are faster but use more memory [2,4,8] (None) | |
| -mat_cholmod_factor <AUTO> | - (choose one of) SIMPLICIAL AUTO SUPERNODAL | |
| -mat_cholmod_supernodal_switch <40> | - flop/nnz_L threshold for switching to supernodal factorization (None) | |
| -mat_cholmod_final_asis <TRUE> | - Leave factors "as is" (None) | |
| -mat_cholmod_final_pack <TRUE> | - Pack the columns when finished (use FALSE if the factors will be updated later) (None) | |
| -mat_cholmod_zrelax <0.8> | - 3 real supernodal relaxed amalgamation parameters (None) | |
| -mat_cholmod_nrelax <4> | - 3 size_t supernodal relaxed amalgamation parameters (None) | |
| -mat_cholmod_prefer_upper <TRUE> | - Work with upper triangular form (faster when using fill-reducing ordering, slower in natural ordering) (None) | |
| -mat_cholmod_print <3> | - Verbosity level (None) |
Note: CHOLMOD is part of SuiteSparse http://faculty.cse.tamu.edu/davis/suitesparse.html