On Apr 5, 2013, at 9:34 AM, Jozsef Bakosi <jbakosi at lanl.gov> wrote:
> Hi folks, > > In switching from 3.1-p8 to 3.3-p6, keeping the same ML ml-6.2.tar.gz, I get > indefinite preconditioner with the newer PETSc version. Has there been > anything > substantial changed around how PCs are handled, e.g. in the defaults? > > I know this request is pretty general, I would just like to know where to > start > looking, where changes in PETSc might be clobbering the (supposedly same) > behavior of ML. The two versions of PETSc are suppose to work with the same ML. Run both with -ksp_view -ksp_monitor_true_residual (forcing KSPSolve to not generate any error by using a -ksp_max_its 2 or something small) and see if there are any differences in the output. Feel free to send us the two outputs if different if you have questions. I cannot think of anything, off the cuff that would cause a change. Barry > > Thanks, > Jozsef
