Dear experts,

I am trying to get the electronic transport of a large system which contains 2604 atoms in the unit cell, within the dftb calculations.

First I tried this setting:

--nodes=1

--ntasks-per-node=24

--cpus-per-task=1

--mem-per-cpu=2540

and the job ran into out-of-memory error.

Then I increased the number of nodes up to 20, leading to 480 cores and 1,219,200 mb total memory. Unfortunately, the calculation ran into the same error again. The attached figure is the memory utilization related to the mentioned job. At the time around 37 minutes, the semi empirical calculation finished, and the transmission calculation starts. Note that, the calculation ran into error at this time.

**UPDATE on 01.11.2021:**

I also tried on a different partition which has larger memory by allocating 8T memory. The same error occurred. Can someone tell me what is the scale of transport calculations with atk? The number of atoms vs memory. Is it a bug or a technical problem?

Appreciate any comments/suggestions

Cheers, A