[petsc-users] GMRES stability

[Orxan Shibliyev]

Hi

I tried to solve Ax=b with my own Gauss-Seidel code and Petsc's GMRES.
With my GS, for a steady state problem I can set CFL=40 and for
unsteady case can set dt=0.1. However, for GMRES I can't set CFL more
than 5 and for unsteady case dt more than 0.00001. I need GMRES for
parallel computations so I cannot use GS for this purpose. Is there a
way to improve the stability of GMRES?