As Matt said you should see the initial 2-norm residual asymptote to a constant with scaling, but it will rise.
I prefer the max norm for this reason. You can use -ksp_monitor_max, but this does compute an extra residual, apparently, but I don't understand why it should ... If this does not asymptotic to constant and your problem is linear, you have a bug. On Mon, Oct 1, 2018 at 6:31 PM Weizhuo Wang <[email protected]> wrote: > Hi! > > I'm recently trying out the example code provided with the KSP solver > (ex12.c). I noticed that the mean norm of the grid increases as I use finer > meshes. For example, the mean norm is 5.72e-8 at m=10 n=10. However at > m=100, n=100, mean norm increases to 9.55e-6. This seems counter intuitive, > since most of the time error should decreases when using finer grid. Am I > doing this wrong? > > Thanks! > -- > Wang Weizhuo >
