[petsc-users] Making the convergence faster

[Maahi Talukder]

Dear All,


I am solving Poisson grid generation equation  using 9-point Finite
Difference. The type of convergence plot I am getting has been attached
herewith. As  the plot shows, at the beginning, the convergence is very
fast, but later the convergence is slowing down. I am using GMRES with left
preconditioning?

My question is, is it normal? Any ideas how  to make the convergence faster?



Thanks,
Maahi Talukder
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20190710/49049f64/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 1.jpg
Type: image/jpeg
Size: 57853 bytes
Desc: not available
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20190710/49049f64/attachment-0001.jpg>