[Wannier] MPI version large systems

[Jonathan Backman]

Dear All,

I'm trying to run Wannier90 using MPI for a large system.

2688 Bloch states, 2048 Wannier functions, and 27 K-points. (3x3x3 grid).

AMN file size: 6 GB

MMN file size: 42 GB

My system does not run out of memory during the parallel run (512 GB 
available).

When using one MPI process then calculation progresses, but very slow 
due to the size.  However, when running using multiple MPI processes  
the calculations runs but does not progress at all, I have tried waiting 
over 2 weeks.  I tried different number of MPI processes, but I would 
assume 27 would be the best since I have 27 k-points.

Does anyone have experience with the MPI version of the code for large 
systems? Are there any specific setting that should be used when running 
using MPI?

Best regards,

Jonathan Backman, ETH Zürich