Preconditioner - CHOLESKY
Usage:
-pc_type cholesky
Options:
-pc_factor_in_place
Form Cholesky in the same memory as the matrix
-pc_factor_fill
Expected non-zeros in Cholesky/non-zeros in matrix. Default = 5
-pc_factor_reuse_fill
Use fill from previous factorization
-pc_factor_reuse_ordering
Reuse ordering from previous factorization
-pc_factor_mat_ordering_type
Reordering to reduce nonzeros in Cholesky (one of):
natural
nd
1wd
rcm
qmd
rowlength-pc_factor_shift_nonzero
Shift added to diagonal
-pc_factor_shift_nonzero
Shift added to diagonal. Default = 0
-pc_factor_shift_positive_definite
Manteuffel shift applied to diagonal
-pc_factor_zeropivot
Pivot is considered zero if less than. Default = 0
Info: Often used for solving linear systems directly using -ksp_type preonly