[petsc-users] How to fix max linear steps in SNES

[Smith, Barry F.]

> On Nov 8, 2018, at 9:06 AM, Yingjie Wu via petsc-users <petsc-users at mcs.anl.gov> wrote:
> 
> Dear Petsc developer:
> Hi,
> I recently debugged my program, which is a two-dimensional nonlinear PDEs problem, and solved by SNES. I find that the residual drop in KSP is slow. I want to fix the number of steps in the linear step, because I can not choose a suitable ksp_rtol. I use the command: -ksp_max_it 200, and I want to fix the number of iterations per ksp. But the program seemed to stop in the first nonlinear step.  
>           
> Linear solve did not converge due to DIVERGED_ITS iterations 200            
> Nonlinear solve did not converge due to DIVERGED_LINEAR_SOLVE iterations 0      
>       
> How can I fix the maximum number of iterations of linear steps without stopping the program before the convergence of the non-linear steps? 

-snes_max_linear_solve_fail    10000000                               (some large number)

   Barry



> 
> Thanks,
> Yingjie