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I want to optimize the TiO2(001) surface with 144 atoms
#SBATCH --nodes=4
#SBATCH --ntasks-per-node=32
Is this amount sufficient for calculation or should it be changed?
Are there any special regularity values ​​of these for surfaces with 100-200 atoms?
For example, for a surface with 100 atoms
#SBATCH --nodes=4
#SBATCH --ntasks-per-node=32
For a surface with 150 atoms
#SBATCH --nodes=6
#SBATCH --ntasks-per-node=32
and others.

Hi Davron,

Generally, these settings depend more on the computer architecture that you're using, rather than VASP. There are normally specific partitions of cores and nodes set up. Then the nodes and ntasks should be tested for your specific system. How many nodes and CPUs per node do you have?

Try single point calculations first to find a good combination of cores and nodes and then, once these have been found, try your optimisation. Additionally, I'd recommend reading the NPAR, NCORE, and KPAR tags in INCAR. We recommend setting NPAR or NCORE for the bands/ orbitals, and then KPAR for the k-points. These determine how VASP splits up the calculation for parallel computing.

There is some advice on the VASP wiki about parallelization: wiki/index.php/Category:Parallelization

Under "Terminology in high-performance computing (HPC)", there is a quick definition of the terminology that we use in VASP, which will help for communicating with your systems administrator.