Using VASP on Sol

VASP 6.4.1 is available on Sol as a module using the MPI implementation MPICH. Here is how you can use it:

1. Start an interactive session with more than one n task:

   $ interactive -n 4 # for 4 mpi ranks (4 cores total) OR $ interactive -n 4 -c 4 # for 4 mpi ranks, each of which get 4 cores (16 cores total)

2. Load the modules for vasp and MPI:

   $ module load vasp/6.4.1 $ module load mpich/4.1.2

3. Change directory to where your VASP input files are, e.g., INCAR, POSCAR...

   $ cd /scratch/$USER/myvaspfiles # change to your own directory!

4. Run vasp_std to test your environment and input files:

   (Hit “control” + “c” to cancel this running vasp instance)

5. Upon verifying that vasp starts and accepts the input, we can start attempts with more resources as we gave previously:

   -np 4 should match the -n value from step 1.
   
   We can see that vasp is now running 4 mpi ranks (4 tasks) and 4 cores per task (distrk)

6. These commands, specifically those from step 2, 3, and 5 are the lines you can use to construct an SBATCH script so that you can run future jobs without doing so interactively.