#2648: Empty ApplyBCs call in LeanBSSNMoL
Reporter: Samuel Cupp Status: new Milestone: Version: Type: bug Priority: major Component: EinsteinToolkit thorn
Comment (by Roland Haas):
The scheduled functions in the ApplyBCs group will not do anything unless there has been a SelectGroupForBCs first though (and no intervening ApplyBCs which clears the selections). SelectGroupForBCs does not have to be immediatedly before the ApplyBCs group though, so there could be a "forgotten" / "hidden" one somewhere earlier in the code. Also if this is during initial data only then this may not be very visible at all if the initial data thorn did fill in data everywhere on all grid points irrespective of them being ghosts, buffer, physical boundary, symmetry boundary or interior points. After ADM2BSSN one usually has to SYNC, extrapolate and apply symmetry boundary conditions (possibly in a very specific order) and the Gamma auxiliary variables of the BSSN system which involve derivatives so cannot be set in ghost zones and the boundary. Most others can be computed point by point, so that a missing SYNC (missing for sure it seems) will only show up a slight change in regions filled via prolongation (but not in inter-processor ghosts or in restriction target region).
-- Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/2648/empty-applybcs-cal...