[gpaw-users] Computational cost of vdW-DF

[Jens Jørgen Mortensen]

On Mon, 2011-04-11 at 23:56 +0200, Duy Le wrote:
> Dear all,
> As I understand, the approach of Román-Pérez and Soler (PRL 2009) has
> been implemented in GPAW.  I wonder why the self-consistent vdW-DF
> calculation is still extremely expensive (3 or 4 times in most of my
> calculations) in comparison to regular GGA-PBE calculation.
> Does any of you experience this slowness? I would like to know the reason.

For a small system with few electrons, the calculation of the vdW-DF
potential will dominate.  With more electrons the vdW-DF part should
become smaller unless you run on so many cores that the parallelization
of the vdW-DF stuff stops scaling.  So, what is your system and how many
cpu's do you use?

Jens Jørgen

> Thank you.
> --------------------------------------------------
> Duy Le
> PhD Student
> Department of Physics
> University of Central Florida.
> 
> "Men don't need hand to do things"
> 
> _______________________________________________
> gpaw-users mailing list
> gpaw-users at listserv.fysik.dtu.dk
> https://listserv.fysik.dtu.dk/mailman/listinfo/gpaw-users