[aspect-devel] aspect release planning

[Timo Heister]

> I think there is nothing inherently mysterious about either
>   steinberger-viscosity
>   steinberger-viscosity-adiabatic
> Their respective first time steps previously already took 30+353 and 30+385
> iterations, and on the new mesh the first one now needs 30+1761 iterations
> -- and the second hits the ceiling of 1891 and explodes. (Subsequent time
> steps are significant cheaper.)
>
> The thing is that I believe this is entirely coincidental. The viscosity of
> both is very inhomogeneous (a picture for one of the cases is attached): the
> viscosity changes by 4 orders of magnitude over 1.5 cells. You have to
> expect that this is slow to converge, we just don't have a particularly good
> solver for these cases (we have open bug reports).

Interesting that the curved cells make the problem more difficult for
the linear solver, though. Do you have an intuition why that is the
case? I would have expected the linear system to be of similar
difficulty if not easier because cell sizes are more regular.

> I don't know what to do with this particular test, but I don't think it
> presents an underlying problem with the patch -- just an underlying problem
> with the solver.

Well, it can be related: we now have a mapping in the interior. Maybe
there is something fishy happening with the mapping or quadrature
point locations in the material model? Who knows.

> You currently hold the master branch for this patch. It doesn't apply
> cleanly to master -- can you rebase it and see which tests still fail?

I rebased and they both crash the same way:
http://cdash.kyomu.43-1.org/testDetails.php?test=4480083&build=2541

(I am fixing the test output for the other tests right now)

-- 
Timo Heister
http://www.math.clemson.edu/~heister/