[petsc-users] How to use multigrid?

[Thomas Witkowski]

:) It was just a question whether is makes sense to run my solver in 
this range of number of cores, or whether AMG by itself will not scale 
here anymore. As my computational time is limited, I have to think 
carefully when using 10^4 cores.

Thomas


Am 09.11.2012 18:40, schrieb Jed Brown:
> Don't speculate, send -log_summary and information about the problem 
> and machine. Some setup operations degrade, but solves should scale 
> pretty well.
>
> On Fri, Nov 9, 2012 at 11:37 AM, Thomas Witkowski 
> <thomas.witkowski at tu-dresden.de 
> <mailto:thomas.witkowski at tu-dresden.de>> wrote:
>
>     While we're at it, can some of you tell me some world about
>     parallel scaling of algebraic multigrid methods? In most of my
>     codes I use them to precondition some simple blocks, e.g. Laplace
>     matrix. I'm pretty sure that parallel scaling of my solver is
>     limited mostly by scaling of the AMG method which is used. What
>     are the expectations, when going to 10^3 or 10^4 cores?
>
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20121109/e4cffacb/attachment-0001.html>