I use the two commands in the same project. The first is divergent while the second is convergent. nohup mpiexec -n 4 ./ex4f -ksp_type bcgs -pc_type bjacobi -ksp_rtol 1.0e-5 -ksp_converged_reason >out.txt & nohup mpiexec -n 8 ./ex4f -ksp_type bcgs -pc_type bjacobi -ksp_rtol 1.0e-5 -ksp_converged_reason >out.txt & So what is the reason? Thanks. Jim
>> 2013-02-07 13:16:51?"Matthew Knepley" <knepley at gmail.com> ??? >> On Thu, Feb 7, 2013 at 12:11 AM, w_ang_temp <w_ang_temp at 163.com> wrote: >> Hello, >> I use the same project, but I find that when different number of >> processors is choosed, >> the convergence is different. For example, when the processors are 4, it is >> divergent; when >> the processors are 8, it is convergent. >> So what is the reason? >It is likely that your preconditioner changed. > Matt >> Thanks. >> Jim. -- 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/20130217/671a6313/attachment.html>
