Qiyue: For linear solvers, bjacobi/ilu(0) is the default PETSc preconditioner. You can change it with option '-pc_type <>', and use '-ksp_view' to check what solver is being used.
Hong Dear All: > When I am solving a linear system. in command line I use: > -ksp_type=cr > then in the output file: > I have : job75557 7959 5e+00 2.8e+02 1.0e-01 2.8e+02 bjacobi blks=128 > ilu lvls=0,order=natural > > When I am using: > -ksp_type cr _pc_type bjacobi > the output file looks the same. > > From the driver source code: > bjacobi blks=128 ilu > is the kspinfo output. > > I am wondering, Does this mean that bjacobi is the default preconditioner > for cr? > > > Thanks > > Qiyue Lu > > > >