On Tue, Oct 20, 2009 at 9:52 AM, <jarunan at ascomp.ch> wrote: > Hello, > > I would like to know some information about GMRES performance in PETSc if > you have any experience. > > I am running a parallel test case(9300 cells) comparing cpu time using by > solvers in Petsc. While BICGSTAB was doing 0.9 sec, GMRES 15 sec with the > same preconditioner(Additive Schwarz). I did not expect that GMRES would be > that much slower. Everything is default. >
I ssume you mean it takes many more iterates. This is certainly possible. > Please share your experiences, how the performance of solvers are in your > test cases. Which option I should set to improve GMRES performance? Is there > the best combination of Preconditioner and solver? > Solvers are highly problem dependent. There is no black box solution. Matt > Thank you very much > Jarunan > > -- > Jarunan Panyasantisuk > Development Engineer > ASCOMP GmbH, Technoparkstr. 1 > CH-8005 Zurich, Switzerland > Phone : +41 44 445 4072 > Fax : +41 44 445 4075 > E-mail: jarunan at ascomp.ch > www.ascomp.ch > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20091020/f7c08ec5/attachment.htm>
