[DFTB-Plus-User] performance on ryzen cpus

[Karol Strutynski]

Hello,
My group have a machines with ryzen EPYC processors. I noticed that
the performance of DFTB+ (version 18.2) is much worse than on
equivalent intel cpu.
I tried various compilers (gcc , ifort, aocc flang) with variation of flags.
The best I got was using intel 2018 compiler with "-O3 -qopenmp -ip
-standard-semantics -heap-arrays 10 -axAVX  -xHost -fast" flags.
The results are usually the same - intel cpu is much faster than EPYC,
in extreme cases the times are almost three times larger.

The other programs compiled on the ryzen present performance similar
to intel machine.

It is quite possible I missed something during optimization. Does
anybody have experience with running dftb+ on amd based machines?

Best Regards,
--
Karol Strutyński
CICECO - Aveiro Institute of Materials
Department of Chemistry
University of Aveiro
Office 29.3.25
3810-193, Aveiro, PORTUGAL
Phone: +48 739259476
Mail: strutynski.karol at gmail.com, skarol at ua.pt
ORCID: http://orcid.org/0000-0001-8733-9012