Unnecessary communication during interpolate, add, assign
Currently (in various DoF spaces) we communicate the halos during the LA routines interpolate, add and assign although it is not strictly necessary since all of them only update the local DoFs and only depend on local DoFs.
It would be more consequent to let routines that need updated halos pull them when necessary (e.g. operators - before stencils are applied).
Resolving this issue
- would clear up which routines really depend on updated halos
- could increase performance as it might safe time that is currently spent on unnecessary communication (however, shifting the communication to other routines could also decrease performance since we might not be able to overlap it with computation in some cases)