My Community

Hello All,
We are trying to build a computer cluster (128 cores) and using VASP 5.2. I would like to get feedback from those who have experienced VASP performance and I appreciate their recommendations for optimizing our system.

We are mainly interested in phonon and electronic band structure calculations. The system sizes will be around 100 atoms.

- Any recommendation in terms of processors types ( Xeon
vs AMD Petron)

- Any recommendation for the network connections (
infinband vs myrinet)

- How does VASP performance scale when using (SDR,QDR,
DDR, 4x,8x,12x) infiniband?

Thank you
IYAD

Hi IYAD,

I'll start bottom up:

- I've got DDR-IB running and observe a loss of about 1% wrt. communication. With GBit-Ethernet it was more like 20-30%. My guess is it does not matter which IB-speed you are actually using. The low latency is enough.
- No idea, check for latency wrt. pricing. You might also have a look if your preferred communication software can handle both protocols.
- Since scaling is not a big issue, got for theoretical peak performance vs. pricing.

My 0.01 ?.

Cheers,

Alex