Fully distributed triangulation with GMSH

[Kumar Saurabh]

Hi, 

I am trying to perform the mesh partition using the mesh generated from GMSH. The generated mesh is quite big with around 500K elements. 

I am new to deal.ii. But I get the impression that the parallel::distributed::Triangulation works only from the quadrilateral/hexahedral meshes and uses p4est backend.

I tried GridTools::partition_triangulation which tends to repeat the elements on all processor. This is not ideal as the number of elements is too large.

I want to ask if I can use parallel::fullydistributed::Triangulation to partition the tetrahedrals without repeating on all the processors. If so, is there any examples for the same. All the examples I saw tends to work for Hypercube type of meshes.

Thanks,

Kumar Saurabh

[Peter Munch]

Hi Kumar,

take a look at https://www.dealii.org/developer/doxygen/deal.II/namespaceTriangulationDescription_1_1Utilities.html#aefc3e841bcfd37714a07d04e42c8ffca.

Hope this helps,
Peter

[Kumar Saurabh]

HI Peter,

Thanks a lot. It seems to work. If I am understanding it correctly, having group size = MPI ranks, means that only proc 0 is reading the data and distributing it. Am I correct? 

Is it possible to verify the size of elements / memory size after the file is read and before the partition to actually verify that only proc 0 is reading and storing before partitioning?

Thanks,

Kumar Saurabh

[blais...@gmail.com]

Dear Kumar,

You can monitor the processes using your OS to verify that.

If you are loading a relatively large triangulation, this will be very apparent since the memory footprint of one process will be significantly larger. Even a quick "top" will enable you to see this.

Best

Bruno

[Kumar Saurabh]

Hi Bruno,

Thanks for the suggestion. It seems to be working fine. 

Thanks,

Kumar Saurabh