[petsc-users] Agglomeration for Multigrid on Unstructured Meshes

[Danyang Su]

Thanks Jed for the quick response. Yes I am asking about the repartitioning of coarse grids in geometric multigrid for unstructured mesh. I am happy with AMG. Thanks for letting me know.

Danyang

On 2020-06-01, 1:47 PM, "Jed Brown" <jed at jedbrown.org> wrote:

    I assume you're talking about repartitioning of coarse grids in
    geometric multigrid -- that hasn't been implemented.

    https://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/PC/PCTELESCOPE.html

    But you can use an algebraic multigrid that does similar communicator
    reduction, and can be applied to the original global problem or just on
    the "coarse" problem of an initial geometric hierarchy.

    Danyang Su <danyang.su at gmail.com> writes:

    > Dear All,
    >
    >  
    >
    > I recalled there was a presentation ‘Extreme-scale multigrid components with PETSc’  taling about agglomeration in parallel multigrid, with future plan to extend to support unstructured meshes. Is this under development or to be added? 
    >
    >  
    >
    > Thanks and regards,
    >
    >  
    >
    > Danyang