[petsc-users] Questions on DMPlexDistribute

[Praveen C]

Dear all

I am trying to understand partitioning using DMPlexDistribute.

I see an option “overlap”. Does this determine how many ghost cells are added ? Are these determined based on face neighboring cells or vertex neighboring cells ? 

In

https://www.mcs.anl.gov/petsc/petsc-current/src/ts/examples/tutorials/ex11.c.html

I see a call to DMPlexConstructGhostCells after DMPlexDistribute. Can you explain the purpose of this and how it is related to overlap ?

After DMPlexDistribute, how can I identify locally owned cells and ghost cells ?

Thanks
praveen