I have specified maximum number of iterations 500 and tolerance 1E-8. Usually it drives the residual to specified tolerance but in this case GMRES seems to stop after 15 iterations and the residual is still above tolerance.
0 KSP Residual norm 2.928143483788e+05 1 KSP Residual norm 1.403875955158e+05 2 KSP Residual norm 4.068852804332e+04 3 KSP Residual norm 8.517044011269e+03 4 KSP Residual norm 2.179034005404e+03 5 KSP Residual norm 6.155723927227e+02 6 KSP Residual norm 1.636241232571e+02 7 KSP Residual norm 4.839052750735e+01 8 KSP Residual norm 1.118719384434e+01 9 KSP Residual norm 3.313977141518e+00 10 KSP Residual norm 7.447603108045e-01 11 KSP Residual norm 1.942386237492e-01 12 KSP Residual norm 4.843647894709e-02 13 KSP Residual norm 1.215264193249e-02 14 KSP Residual norm 3.111716140560e-03 15 KSP Residual norm 7.922640853896e-04 Matrix p Number of iterations: 15 Residual: +7.922641E-04 Anyone knows why this happens? Billy.
