adaptive solver demo (auto-adaptive-poisson) fails to run in parallel

[Drew Parsons]

The auto-adaptive-poisson demo fails to run in parallel, giving the error message:

Traceback (most recent call last):
  File "demo_auto-adaptive-poisson.py", line 253, in <module>
    solver.solve(tol)
  File "/usr/lib/python3/dist-packages/dolfin/fem/adaptivesolving.py", line 81, in solve
    cpp.AdaptiveLinearVariationalSolver.solve(self, tol)
RuntimeError: 

*** -------------------------------------------------------------------------
*** DOLFIN encountered an error. If you are not able to resolve this issue
*** using the information listed below, you can ask for help at
***
***     [e-mail]
***
*** Remember to include the error message listed below and, if possible,
*** include a *minimal* running example to reproduce the error.
***
*** -------------------------------------------------------------------------
*** Error:   Unable to perform operation in parallel.
*** Reason:  Extrapolation of functions is not yet working in parallel.
***          Consider filing a bug report at https://bitbucket.org/fenics-project/dolfin/issues.
*** Where:   This error was encountered inside log.cpp.
*** Process: 0
*** 
*** DOLFIN version: 2017.1.0
*** Git changeset:  unknown
*** -------------------------------------------------------------------------

The first iteration finishes successfully, the error occurs when preparing for the second adaptive iteration.

[Chris Richardson]

This is known not to work in parallel. Any suggestions for a suitable fix would be welcome.

[Drew Parsons]

Thanks for the confirmation of status. Good fodder for a PhD project.

[Alexander Gary Zimmerman]

How big of a project are we looking at here? Are we just missing parallel extrapolation of functions? What in particular makes this more difficult to implement in parallel than other FEniCS features?

I have been wanting to dig into this question for a while now. Is there already a nice summary anywhere that would help me better understand it? Or do I just start by looking at the code?