[Wannier] wannier90 + vasp initial projections parallelism
Aron Szabo
szaboa at iis.ee.ethz.ch
Tue Jan 13 11:55:39 CET 2015
Dear Wannier90 developers,
I'm using vasp 5.3 and wannier90 2.0. I've noticed that the calculation
of the initial projections for the wannierization in vasp is sequential,
it doesn't speed up with the increasing number of cpu-s. For large
systems I'm calculating separately smaller sets of projections to
emulate some parallelism, but there is a huge overhead from calculating
the overlaps first in each case. It can take 1-2 days just to start
calculating the projections when I have 2-300 atoms (1-2000 bands). So
generating the projections can take more time than the actual
wannierization. If the calculation of the overlaps could be somehow
switched off, it would already solve this problem practically, because
then the calculation of the projections would scale nicely, and the
overlaps could be calculated in a separate run. I'm not good in fortran,
so I'm asking you whether it could be done maybe by just commenting out
a few lines somewhere either in vasp's or wannier90's code, and if so,
where is it exactly? I'm also interested if it is planned at all to
parallelize the wannierization sometimes in the future, or is the
problem itself something that's not possible to parallelize efficiently?
Thanks in advance,
Aron Szabo
PhD student at IIS, ETH Zurich
More information about the Wannier
mailing list