Ah, I was just busy writing what Wolfgang said. You can find more info on custom partitions for parallel::shared::Triangulation here: https://dealii.org/current/doxygen/deal.II/classparallel_1_1shared_1_1Triangulation.html#a686a3453dfec098eb64d1510aa1716e1 <https://dealii.org/current/doxygen/deal.II/classparallel_1_1shared_1_1Triangulation.html#a686a3453dfec098eb64d1510aa1716e1>
You might also be able to “encourage” another partitioning using cell weights, but this was more aimed at load balancing in an hp-FEM context: https://dealii.org/current/doxygen/deal.II/classparallel_1_1CellWeights.html <https://dealii.org/current/doxygen/deal.II/classparallel_1_1CellWeights.html> https://dealii.org/current/doxygen/deal.II/structTriangulation_1_1Signals.html#af58294e40c64257c9de55e78b6443e36 <https://dealii.org/current/doxygen/deal.II/structTriangulation_1_1Signals.html#af58294e40c64257c9de55e78b6443e36> I hope that this helps, Jean-Paul > On 15 Sep 2020, at 22:46, Wolfgang Bangerth <bange...@colostate.edu> wrote: > > On 9/14/20 7:29 PM, shahab.g...@gmail.com wrote: >> I am using load balancing and I noticed after load balancing, that the cells >> owned by each processor are sometimes separated from each other. In other >> words, some processors may own cell domains that are not connected to each >> other. >> As this increases the computational cost in my case, I was wondering whether >> it would be possible to limit the load balancing to define only adjacent >> cells? > > Not with parallel::distributed::Triangulation. That class uses a partitioning > algorithm that optimizes for the data structures used in storing > triangulations, sometimes at the expense of creating these kinds of > disconnected sub-domains. In practice, however, this has relatively little > effect on the performance of programs to the best of our knowledge: Yes, it > is not *optimal*, but it is good enough to not be a major problem in most > cases. You state that it increases the computational cost -- that's true, but > do you have evidence that that creates a bottleneck? > > If you do need a different partitioning algorithm, you can use > parallel::shared::Triangulation or, since deal.II 9.2, the > parallel::fullydistributed::Triangulation class. > > Best > W. > > -- > ------------------------------------------------------------------------ > Wolfgang Bangerth email: bange...@colostate.edu > www: http://www.math.colostate.edu/~bangerth/ > > -- > The deal.II project is located at http://www.dealii.org/ > For mailing list/forum options, see > https://groups.google.com/d/forum/dealii?hl=en > --- You received this message because you are subscribed to the Google Groups > "deal.II User Group" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to dealii+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/dealii/e8d17b06-a23c-c00a-1d8c-c3cc11464bb4%40colostate.edu. -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to dealii+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/E8672DB8-50A8-46A3-BBB0-D57FBE3C715F%40gmail.com.
