[petsc-users] about linear solver convergence

[Barry Smith]

http://www.mcs.anl.gov/petsc/petsc-as/documentation/faq.html#kspdiverged


On Oct 11, 2011, at 9:45 AM, behzad baghapour wrote:

> Dear all,
> 
> I set my Jacobian matrix in petsc and test it to ensure for correctness for Jacobian and RHS function. ( also precondition = jacobian )
> I have solved my problem before with some other solvers (gmers/ILU(2)) and the convergence has been achieved within 15 - 16 iterations.
> 
> But in petsc the linear solver (ksp=GMRES) is not converged within this number ( or may be converged in more than 700 iterations!!! ). I know that I should have a mistake but I can't predict it?
> 
> Please help me what parts of petsc solver I should check?
> 
> Regards,
> Behzad
> 
> -- 
> ==================================
> Behzad Baghapour
> Ph.D. Candidate, Mechecanical Engineering
> University of Tehran, Tehran, Iran
> https://sites.google.com/site/behzadbaghapour
> Fax: 0098-21-88020741
> ==================================
>