Using DoFRenumbering::Cuthill_McKee and DoFRenumbering::component_wise in parallel

[Nihar Bhardwaj Darbhamulla]

Can we deploy these sequentially after a parallel partitioning of the mesh i.e. if we have an object of type

parallel::distributed::Triangulation<dim> triangulation;

and we subsequently ask the dof_handler object to distribute the degrees of freedom as follows

dof_handler.distribute_dofs(fe);

can we proceed to renumber the DoFs with Cuthill_McKee and component_wise? Does this create a bandwidth minimized component_wise renumbered sparsity structure for each process.

I have this question because when I'm using the serial version of triangulation, I'm explicitly calling subdomain_wise renumbering first and then Cuthill-McKee and component_wise renumbering on 4 processes, I can see 4 bandwidth minimized structures which might illustrate that the renumbering retained the individual partition identity.

Best,

Nihar

[Wolfgang Bangerth]

On 9/26/24 13:47, Nihar Bhardwaj Darbhamulla wrote:
>
> parallel::distributed::Triangulation<dim>
> <https://www.dealii.org/current/doxygen/deal.II/classparallel_1_1distributed_1_1Triangulation.html> triangulation <https://www.dealii.org/current/doxygen/deal.II/p4est__wrappers_8cc.html#ace00f2f80d9780ef9aa1007e1c22c6a4>;

> and we subsequently ask the dof_handler object to distribute the degrees of
> freedom as follows
>
> dof_handler.distribute_dofs(fe);
>
> can we proceed to renumber the DoFs with Cuthill_McKee and component_wise?
> Does this create a bandwidth minimized component_wise renumbered sparsity
> structure for each process.
>
> I have this question because when I'm using the serial version of
> triangulation, I'm explicitly calling subdomain_wise renumbering first and
> then Cuthill-McKee and component_wise renumbering on 4 processes, I can see 4
> bandwidth minimized structures which might illustrate that the renumbering
> retained the individual partition identity.

Nihar: I believe that this should work. What happens if you try?

Best
W.

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Wolfgang Bangerth email: bang...@colostate.edu
www: http://www.math.colostate.edu/~bangerth/