[Libmesh-devel] MeshCommunication::allgather()

[Derek G. <fri...@gm...>]

Quick question about MeshCommunication::allgather()... it looks like it is
doing an all-to-all broadcast.. is that true?

We utilize this in the output system when we're trying to output a
ParallelMesh using a serial format (like Exodus).  In that case we really
don't need the mesh on _every_ processor.... only on processor 0.

It would be better to use something like
MeshCommunication::localize_to_one() to bring the mesh down to processor 0
and output it then get rid of the remote elements again (like what
MeshSerializer does, but not all-to-all).

Does that make sense to you guys?

I understand that we shouldn't really be using a serial output format with
ParallelMesh... but there are times when it's going to happen so no reason
to be so wasteful ;-)

Derek