#!/bin/bash -l # Just increase this number of you need more nodes. #SBATCH -N 1 #SBATCH -t 03:00:00 #SBATCH -q regular #SBATCH -C haswell #SBATCH -J #SBATCH -A #SBATCH -e error.txt #SBATCH -o output.txt # one MPI rank per half-socket (see below) #SBATCH --tasks-per-node=4 # request all logical (virtual) cores per half-socket #SBATCH --cpus-per-task=16 # each Cori Haswell node has 2 sockets of Intel Xeon E5-2698 v3 # each Xeon CPU is divided into 2 bus rings that each have direct L3 access export WARPX_NMPI_PER_NODE=4 # each MPI rank per half-socket has 8 physical cores # or 16 logical (virtual) cores # over-subscribing each physical core with 2x # hyperthreading leads to a slight (3.5%) speedup # the settings below make sure threads are close to the # controlling MPI rank (process) per half socket and # distribute equally over close-by physical cores and, # for N>8, also equally over close-by logical cores export OMP_PROC_BIND=spread export OMP_PLACES=threads export OMP_NUM_THREADS=16 # for async_io support: (optional) export MPICH_MAX_THREAD_SAFETY=multiple EXE="" srun --cpu_bind=cores -n $(( ${SLURM_JOB_NUM_NODES} * ${WARPX_NMPI_PER_NODE} )) ${EXE}