diff --git a/pytest-mpi b/pytest-mpi
index b661bf84..97a817ce 100755
--- a/pytest-mpi
+++ b/pytest-mpi
@@ -82,7 +82,7 @@ else
   fi
 
   if [ "${ORDEROUTPUT}" -eq 1 ]; then
-    mpirun -n ${NPROCS} --output-filename outtest pytest ${PYTEST_ARGS} --only-mpi >/dev/null
+    mpirun -n ${NPROCS} --oversubscribe --output-filename outtest pytest ${PYTEST_ARGS} --only-mpi >/dev/null
     exit_code=$?
     for ((RANK=0; RANK<${NPROCS}; RANK++)); do
       RANKFILE="outtest/1/rank.${RANK}/stdout"
@@ -94,10 +94,10 @@ else
     done
     rm -r outtest
   elif [ "${UNMUTE}" -eq -1 ]; then
-    mpirun -n ${NPROCS} pytest ${PYTEST_ARGS} --only-mpi
+    mpirun -n ${NPROCS} --oversubscribe pytest ${PYTEST_ARGS} --only-mpi
     exit_code=$?
   else
-    mpirun -n ${NPROCS} utils/mute_all_ranks_except.sh ${UNMUTE} pytest ${PYTEST_ARGS} --only-mpi
+    mpirun -n ${NPROCS} --oversubscribe utils/mute_all_ranks_except.sh ${UNMUTE} pytest ${PYTEST_ARGS} --only-mpi
     exit_code=$?
   fi
 fi