Non repeatability issue

> 1) Are you sure the -vecscatter_reproduce is working, run with - > options_left and see if > says the option was not used. I have harwired it into the 2.3.3-p8, following your suggestion. > 2) did you do the -ksp_rtol 1.e-12 at the same time as the - > vecscatter_reproduce? They > must be do

MG preconditioner issue

On Tue, Mar 18, 2008 at 5:00 PM, Matt Funk wrote: > Hi, > > i am trying out the MG preconditioner in PETSc and am encountering some > issues. In fact when i use the MG preconditioner i get a segmentation > violation. This does not happen with other preconditioners. If you just do something lik

MG preconditioner issue

Hi, i am trying out the MG preconditioner in PETSc and am encountering some issues. In fact when i use the MG preconditioner i get a segmentation violation. This does not happen with other preconditioners. Running Petsc in debug mode with the -info option did not seem to produce any useful dat

Non repeatability issue

> > > 1) You have way too many Newton steps. Newton is quadratically >convergent, so if > you have 100+ steps, it means you are very very far from the >solution when you > begin. In this region, Newton is a really bad algorithm and can >be very very > sensitive to perturbations. I wo

Non repeatability issue

On Mar 18, 2008, at 11:52 AM, Aldo Bonfiglioli wrote: >> 1) Are you sure the -vecscatter_reproduce is working, run with - >> options_left and see if >> says the option was not used. > > > I have harwired it into the 2.3.3-p8, following your suggestion. > >> 2) did you do the -ksp_rtol 1.e-12 at

Non repeatability issue

available URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20080318/f7a42250/attachment.pdf> -- next part -- A non-text attachment was scrubbed... Name: vecscatter_reproduce.pdf Type: application/pdf Size: 13056 bytes Desc: not available URL: <http

Non repeatability issue

1) Are you sure the -vecscatter_reproduce is working, run with - options_left and see if says the option was not used. 2) did you do the -ksp_rtol 1.e-12 at the same time as the - vecscatter_reproduce? They must be done together. 3) what happens on 1 process? Does it behave exactly the same fo

Non repeatability issue

To me this looks like 1) You have way too many Newton steps. Newton is quadratically convergent, so if you have 100+ steps, it means you are very very far from the solution when you begin. In this region, Newton is a really bad algorithm and can be very very sensitive to pertur