diff --git a/benchmark-slow/job-aps.sh b/benchmark-slow/job-aps.sh
index a9d8c0f447a1853c066c39d9d463484ca2cedaab..4bc9d94e73d431d87ab926b3d2a8da6b69a664d4 100644
--- a/benchmark-slow/job-aps.sh
+++ b/benchmark-slow/job-aps.sh
@@ -24,5 +24,5 @@ pushd swiftsim/examples/PMillennium/PMillennium-768
 export MPS_STAT_LEVEL=2
 export APS_ARGS="--collection-mode=mpi,omp"
 
-mpirun -np 1 aps $APS_ARGS ../../swift_mpi --cosmology --self-gravity -v 1 --threads=64 -n 1 -P Restarts:enable:0 -PInitialConditions:file_name:/cosma5/data/do008/dc-fraw1/swift_initial_conditions/pmillenium/PMill-768.hdf5 p-mill-768.yml
+mpirun -np $SLURM_NTASKS aps $APS_ARGS ../../swift_mpi --cosmology --self-gravity -v 1 --threads=64 -n 1 -P Restarts:enable:0 -PInitialConditions:file_name:/cosma5/data/do008/dc-fraw1/swift_initial_conditions/pmillenium/PMill-768.hdf5 p-mill-768.yml
 
diff --git a/benchmark-slow/job-arm.sh b/benchmark-slow/job-arm.sh
index 64c3ef9c198a0faec831d86666fe6e58d24b5800..8f529cd1f2a69845d67e1a58e8e50d606c8cdfeb 100644
--- a/benchmark-slow/job-arm.sh
+++ b/benchmark-slow/job-arm.sh
@@ -20,5 +20,5 @@ module load python/3.6.5
 module load allinea/ddt/20.2.1
 pushd swiftsim/examples/PMillennium/PMillennium-768
 
-perf-report --mpi=intel-mpi -np 1 ../../swift_mpi --cosmology --self-gravity -v 1 --threads=64 -n 1 -P Restarts:enable:0 -PInitialConditions:file_name:/cosma5/data/do008/dc-fraw1/swift_initial_conditions/pmillenium/PMill-768.hdf5 p-mill-768.yml
+perf-report --mpi=intel-mpi -np $SLURM_NTASKS ../../swift_mpi --cosmology --self-gravity -v 1 --threads=64 -n 1 -P Restarts:enable:0 -PInitialConditions:file_name:/cosma5/data/do008/dc-fraw1/swift_initial_conditions/pmillenium/PMill-768.hdf5 p-mill-768.yml