Re: [Libmesh-users] how to read a distributed mesh

[Roy S. <roy...@ic...>]

On Sat, 9 Dec 2017, Jahrul Alam wrote:

> Nemesis IO reads the mesh in parallel (not the solution); however,
> the reader destroys the multi-level structure of the mesh. Is there
> a work around to handle this problem?

I'm afraid not; not even ExodusII ("serial Nemesis") lets us store AMR
structure.  IIRC when we tried the result was awful on visualization
programs, which would try to display the inactive elements too and
naturally show garbage.  https://en.wikipedia.org/wiki/Z-fighting

For archival of AMR meshes our only good solution right now is
serialized Xdr, I believe.  If that's a performance problem, you could
output CheckpointIO during your simulation runs, then postprocess
convert to Xdr later.  At some point we'll also make CheckpointIO a
first-class format with forwards compatibility, but that's a pain to
maintain while the format is still in flux so it won't happen soon.
---
Roy