Run instructions for CP2K. 2016-10-26 After building the hybrid MPI+OpenMP version of CP2K you have an executable called cp2k.psmp. The general way to run the benchmarks is: export OMP_NUM_THREADS=## parallel_launcher launcher_options path_to_cp2k.psmp -i inputfile -o logfile Where: o The parallel_launcher is mpirun, mpiexec, or some variant such as aprun on Cray systems or srun when using Slurm. o The launcher_options include the parallel placement in terms of total numbers of nodes, MPI ranks/tasks, tasks per node, and OpenMP threads per task (which should be equal to the value given to OMP_NUM_THREADS) You can try any combination of tasks per node and OpenMP threads per task to investigate absolute performance and scaling on the machine of interest. For tier-1 systems the best performance is usually obtained with pure MPI,while for tier-0 systems the best performance is typically obtained using 1 MPI task per node with the number of threads being equal to the number of cores per node. More information in the form of a README and an example job script is included in each benchmark tar file. The run walltime is reported near the end of logfile: grep "CP2K " logfile | awk -F ' ' '{print $7}'