Re: [Libmesh-devel] Bug in Partitioner::_set_node_processor_ids()?

[Benjamin K. <ben...@na...>]

>>> Okay, it's fixed.  In theory, ParallelMesh should now work in serial
>>> for all codes and in parallel (i.e. after deleting non-semilocal
>>> elements) for most non-adaptive codes.  In practice, I've changed
>>> enough DofMap code that I may have even broken SerialMesh.  Pay close
>>> attention to make sure nothing's gone wonky after
>> 
>> What is required to properly do this?  I've simply replaced Mesh with
>> ParallelMesh in ex4, (my favorite parallel whipping boy) and am getting a
>> segfault when the equation systems initialize.  I assume I'm missing a key
>> renumber_nodes... / find_neighbors combination.
> 
> Hmm... ex4 seems to be running fine for me, but I can't guarantee that
> it'll do the same for you; ex6 was triggering assert() failures for me
> in MeshCommunication::allgather().  If you run with -dbg=gdb as an
> mpirun argument, can you get a stack trace on the segfault?

--enable-parmesh fixed ex4 for me, sort of...

The issue is that running in parallel does not reduce the size of the
elements/nodes containers after equation_systems.init().  I added a
mesh.print_info() after equation_systems.init() and ran
$ mpiexec -n 2 ./ex4-devel -d 3 -n 10

elfboy(20)$ mpiexec -n 2 ./ex4-dbg -d 3 -n 10
Running ./ex4-dbg -d 3 -n 10

 Mesh Information:
  mesh_dimension()=3
  spatial_dimension()=3
  n_nodes()=9261
    n_local_nodes()=4889
  n_elem()=1000
    n_local_elem()=500
    n_active_elem()=1000
  n_subdomains()=1
  n_processors()=2
  processor_id()=0

 EquationSystems
  n_systems()=1
   System "Poisson"
    Type "LinearImplicit"
    Variables="u" 
    Finite Element Types="LAGRANGE", "JACOBI_20_00"
    Infinite Element Mapping="CARTESIAN"
    Approximation Orders="SECOND", "THIRD"
    n_dofs()=9261
    n_local_dofs()=4889
    n_constrained_dofs()=0
    n_vectors()=1

 Mesh Information:
  mesh_dimension()=3
  spatial_dimension()=3
  n_nodes()=9261
    n_local_nodes()=4889
  n_elem()=1000
    n_local_elem()=500
    n_active_elem()=624
  n_subdomains()=1
  n_processors()=2
  processor_id()=0

Or is this the intended behavior?