QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: esp on September 14, 2012, 21:39

Title: ldos best setup
Post by: esp on September 14, 2012, 21:39

I need to know what is the best setup for doing lddos calculations on graphene devices ... more nodes? serial? more memory? 51 k points instead of 101?  it takes forever to run this calc and i need to speed it up ... hard to be productive ... i have a choice between different machines with different specs ..

it takes something like 12 hours for -3 to 3eV in increments of 0.2, at only one bias cfg

Title: Re: ldos best setup
Post by: Anders Blom on September 15, 2012, 00:31

The systems I have done this on before have been cases with 3x3 k-points, so it hasn't been a real problem to me. But I can see 10 k-points changes things a lot.

The calculation time should be virtually linear in number of nodes, so that would be one way. And, inversely, it's also linear in k-points. So reducing k-points by 2 and nodes by 10, you should have a 20x speedup (give or take). Also, maybe you don't need such high resolution or long energy range.