Indicate the amount of fill you expect in the factored matrix, fill = number nonzeros in factor/number nonzeros in original matrix.
PetscErrorCode PCFactorSetFill(PC pc,PetscReal fill)
Not Collective, each process can expect a different amount of fill
|pc ||- the preconditioner context
|fill ||- amount of expected fill
Options Database Key
|-pc_factor_fill <fill> ||- Sets fill amount
For sparse matrix factorizations it is difficult to predict how much
fill to expect. By running with the option -info PETSc will print the
actual amount of fill used; allowing you to set the value accurately for
future runs. Default PETSc uses a value of 5.0
This parameter has NOTHING to do with the levels-of-fill of ILU(). That is set with PCFactorSetLevels() or -pc_factor_levels.
ImplementationsPCFactorSetFill_Factor in src/ksp/pc/impls/factor/factimpl.c
Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages