Hi Matt,
https://arxiv.org/pdf/1907.02604.pdf On Mon, Nov 25, 2019 at 7:54 PM Matthew Knepley <[email protected]> wrote: > On Mon, Nov 25, 2019 at 6:25 PM Swarnava Ghosh <[email protected]> > wrote: > >> Dear PETSc users and developers, >> >> I am working with dmplex to distribute a 3D unstructured mesh made of >> tetrahedrons in a cuboidal domain. I had a few queries: >> 1) Is there any way of ensuring load balancing based on the number of >> vertices per MPI process. >> > > You can now call DMPlexRebalanceSharedPoints() to try and get better > balance of vertices. > > Thank you for pointing out this function! > 2) As the global domain is cuboidal, is the resulting domain decomposition >> also cuboidal on every MPI process? If not, is there a way to ensure this? >> For example in DMDA, the default domain decomposition for a cuboidal domain >> is cuboidal. >> > > It sounds like you do not want something that is actually unstructured. > Rather, it seems like you want to > take a DMDA type thing and split it into tets. You can get a cuboidal > decomposition of a hex mesh easily. > Call DMPlexCreateBoxMesh() with one cell for every process, distribute, > and then uniformly refine. This > will not quite work for tets since the mesh partitioner will tend to > violate that constraint. You could: > > No, I have an unstructured mesh that increases in resolution away from the center of the cuboid. See Figure: 5 in the ArXiv paper https://arxiv.org/pdf/1907.02604.pdf for a slice through the midplane of the cuboid. Given this type of mesh, will dmplex do a cuboidal domain decomposition? Sincerely, SG > a) Prescribe the distribution yourself using the Shell partitioner type > > or > > b) Write a refiner that turns hexes into tets > > We already have a refiner that turns tets into hexes, but we never wrote > the other direction because it was not clear > that it was useful. > > Thanks, > > Matt > > >> Sincerely, >> SG >> > > > -- > What most experimenters take for granted before they begin their > experiments is infinitely more interesting than any results to which their > experiments lead. > -- Norbert Wiener > > https://www.cse.buffalo.edu/~knepley/ > <http://www.cse.buffalo.edu/~knepley/> >
