petsc-3.14.6 2021-03-30

SNESSetLagPreconditionerPersists

Set whether or not the preconditioner lagging persists through multiple solves

Synopsis

#include "petscsnes.h"  
PetscErrorCode  SNESSetLagPreconditionerPersists(SNES snes,PetscBool flg)

Logically Collective on SNES

Input Parameter

	snes	- the SNES context
	flg	- preconditioner lagging persists if true

Options Database Keys

	-snes_lag_jacobian_persists <true,false>	- sets the persistence
	-snes_lag_jacobian <	- 2,1,2,...> - sets the lag
	-snes_lag_preconditioner_persists <true,false>	- sets the persistence
	-snes_lag_preconditioner <	- 2,1,2,...> - sets the lag

Notes

This is useful both for nonlinear preconditioning, where it's appropriate to have the preconditioner be stale by several solves, and for implicit time-stepping, where preconditioner lagging in the inner nonlinear solve over several timesteps may present huge efficiency gains.

Level

developer

Location

src/snes/interface/snes.c
Index of all SNES routines
Table of Contents for all manual pages
Index of all manual pages