diff --git a/tests/test_simple_shear_3d.py b/tests/test_simple_shear_3d.py
index 41a5e864..341984e3 100644
--- a/tests/test_simple_shear_3d.py
+++ b/tests/test_simple_shear_3d.py
@@ -166,6 +166,9 @@ def test_direction_change(
                 switch_time_Ma * 1e6,
                 _id,
             )
+            if HAS_RAY:
+                ray.init(address="auto")
+                _log.info("using Ray cluster with %s", ray.cluster_resources())
             with Pool(processes=ncpus) as pool:
                 for s, out in enumerate(pool.imap_unordered(_run, _seeds)):
                     olivine, enstatite = out
diff --git a/tools/pbs_scripts/run_test_ray_cluster_setup.sh b/tools/pbs_scripts/run_test_ray_cluster_setup.sh
new file mode 100755
index 00000000..25b87f17
--- /dev/null
+++ b/tools/pbs_scripts/run_test_ray_cluster_setup.sh
@@ -0,0 +1,22 @@
+#!/bin/bash
+#PBS -P xd2
+#PBS -q normalbw
+#PBS -l walltime=00:10:00
+#PBS -l ncpus=56
+#PBS -l mem=256GB
+#PBS -l jobfs=400GB
+#PBS -l storage=scratch/xd2+gdata/xd2
+#PBS -l wd
+#PBS -o test_ray_cluster_setup.log
+#PBS -e test_ray_cluster_setup.err
+#PBS -N test_ray_cluster_setup
+
+module purge
+module load python3/3.11.7 python3-as-python
+# NOTE: First run pip install 'ray[default]' in this python environment.
+
+source pbs_start_ray_cluster.sh
+
+python -c 'import ray; ray.init(address="auto"); print(f"nodes in cluster: {ray.nodes()}"); print(f"cluster resources: {ray.cluster_resources()}")'
+
+ray stop
diff --git a/tools/pbs_start_ray_cluster.sh b/tools/pbs_start_ray_cluster.sh
new file mode 100755
index 00000000..d7f509e3
--- /dev/null
+++ b/tools/pbs_start_ray_cluster.sh
@@ -0,0 +1,129 @@
+#!/bin/bash
+set -u
+readonly SCRIPTNAME="${0##*/}"
+usage() {
+    printf 'Usage: source %s\n' "$SCRIPTNAME"
+    echo
+    echo "Source this script in your PBS job file to set up a Ray cluster."
+    echo "Stop the Ray cluster with 'ray stop' as the terminal line of the job."
+    echo "If the environment variable RAY_NWORKERS is set to an integer,"
+    echo "only that many workers will be started. Otherwise, the number of"
+    echo "workers will be set to PBS_NCPUS."
+}
+warn() { >&2 printf '%s\n' "$SCRIPTNAME: $1"; }
+
+# Check for the main prerequisites.
+[ $# -gt 0 ] && { usage; exit 1; }
+module prepend-path PATH "$HOME/.local/bin"
+command -v ray || { warn "unknown command 'ray'"; exit 1; }
+[ -x "pbs_start_ray_worker.sh" ] || { warn "cannot execute pbs_start_ray_worker.sh"; exit 1; }
+
+# https://docs.ray.io/en/latest/cluster/vms/user-guides/large-cluster-best-practices.html
+ulimit -n 65535
+
+USER_CFG=$PBS_O_WORKDIR/.cfg_${PBS_JOBID}
+
+NWORKERS=${RAY_NWORKERS:-${PBS_NCPUS}}
+NGPUS=$((PBS_NGPUS/PBS_NNODES))
+NCPUS=$((NWORKERS/PBS_NNODES))
+unset NWORKERS
+
+# Choose Ray scheduler port in the range 8701-8800.
+SCHEDULER_PORT=$(shuf -n 1 -i 8701-8800)
+while  `ss -lntupw | grep -q ":$SCHEDULER_PORT" >& /dev/null`; do
+    SCHEDULER_PORT=$(shuf -n 1 -i 8701-8800)  # SCHEDULER_PORT is taken.
+done
+
+# Choose Ray dashboard port in the range 8801-8900.
+DASH_PORT=$(shuf -n 1 -i 8801-8900)
+while  `ss -lntupw | grep -q ":$DASH_PORT" >& /dev/null`; do
+    DASH_PORT=$(shuf -n 1 -i 8801-8900)  # DASH_PORT is taken.
+done
+
+LOG_FILE=${USER_CFG}/head_node.log
+if [ ! -d ${USER_CFG} ]; then
+    mkdir ${USER_CFG}
+fi
+touch $LOG_FILE
+
+# Each node needs to load the modules as well.
+module save ${USER_CFG}/module_coll
+echo "#!/bin/bash" >${USER_CFG}/jobpython
+echo "module restore  ${USER_CFG}/module_coll" >> ${USER_CFG}/jobpython
+echo "module prepend-path PATH $HOME/.local/bin" >> ${USER_CFG}/jobpython
+echo " python \$* " >> ${USER_CFG}/jobpython
+chmod 755  ${USER_CFG}/jobpython
+
+# Parameters used to wait for Ray worker connection.
+TIMEOUT=300
+INTERVAL=2
+
+IP_PREFIX=`hostname -i`
+IP_HEAD=${IP_PREFIX}:${SCHEDULER_PORT}
+
+# Set resource numbers (per worker) for ray workers to pick up.
+echo ${IP_HEAD} > ${USER_CFG}/ip_head
+echo ${NGPUS} > ${USER_CFG}/ngpus
+echo ${NCPUS} > ${USER_CFG}/ncpus
+if [ ${PBS_NGPUS} -gt 0 ]; then
+    GPU_MEM=$(( PBS_VMEM / PBS_NNODES / NGPUS))
+    echo ${GPU_MEM} > ${USER_CFG}/mem_proc
+else
+    PROC_MEM=$(( PBS_VMEM / PBS_NNODES / NCPUS))
+    echo ${PROC_MEM} > ${USER_CFG}/mem_proc
+fi
+
+# Start Ray scheduler on the head node.
+ray start --head --node-ip-address=${IP_PREFIX} --port=${SCHEDULER_PORT}  \
+    --dashboard-host=${IP_PREFIX}  --dashboard-port=${DASH_PORT} --num-cpus ${NCPUS} --num-gpus ${NGPUS} &>> ${LOG_FILE}
+
+((t = TIMEOUT))
+while [ ! -f ${LOG_FILE} ]; do
+    sleep ${INTERVAL}
+    ((t -= INTERVAL))
+    while ((t <= 2)); do
+        warn "scheduler failed to start up within $TIMEOUT seconds, aborting."
+        exit 1
+    done
+done
+
+((t = TIMEOUT))
+while ! grep "Ray runtime started." ${LOG_FILE} >& /dev/null; do
+    sleep ${INTERVAL}
+    ((t -= INTERVAL))
+    while ((t <= 2)); do
+        warn "no ray runtime established within $TIMEOUT seconds, aborting"
+        exit 1
+    done
+done
+
+# File to store the ssh command that connects to the Ray head node.
+if [ ! -e ${USER_CFG}/client_cmd  ]; then
+    echo "ssh -N -L $DASH_PORT:`hostname`:$DASH_PORT ${USER}@gadi.nci.org.au " >& $USER_CFG/client_cmd
+else
+    echo "ssh -N -L $DASH_PORT:`hostname`:$DASH_PORT ${USER}@gadi.nci.org.au " >> $USER_CFG/client_cmd
+fi
+
+TOT_NPROCS=0
+# Start Ray workers on the remaining nodes.
+for node in `cat $PBS_NODEFILE | uniq`; do
+    if [ $node != `hostname` ]; then
+        pbs_tmrsh ${node} "${PBS_O_WORKDIR}/pbs_start_ray_worker.sh" &
+    fi
+    if [ ${PBS_NGPUS} -gt 0 ]; then
+        TOT_NPROCS=$(( $TOT_NPROCS + $NGPUS ))
+    else
+        TOT_NPROCS=$(( $TOT_NPROCS + $NCPUS ))
+    fi
+done
+
+echo "========== RAY cluster resources =========="
+if [ ${PBS_NGPUS} -gt 0 ]; then
+    echo "RAY NODE: GPU"
+    echo "RAY WORKERS: ${NGPUS}/Node, ${TOT_NPROCS} in total."
+    echo "RAY MEMORY: $(( GPU_MEM /1024/1024/1024 ))GiB/worker, $(( PBS_VMEM /1024/1024/1024 ))GiB in total."
+else
+    echo "RAY NODE: CPU"
+    echo "RAY WORKERS: ${NCPUS}/Node, ${TOT_NPROCS} in total."
+    echo "RAY MEMORY: $(( PROC_MEM /1024/1024/1024 ))GiB/worker, $(( PBS_VMEM /1024/1024/1024 ))GiB in total."
+fi
diff --git a/tools/pbs_start_ray_worker.sh b/tools/pbs_start_ray_worker.sh
new file mode 100755
index 00000000..e54a0568
--- /dev/null
+++ b/tools/pbs_start_ray_worker.sh
@@ -0,0 +1,24 @@
+#!/bin/bash
+set -e
+readonly SCRIPTNAME="${0##*/}"
+warn() { >&2 printf '%s\n' "$SCRIPTNAME: $1"; }
+[ $# -gt 0 ] && { warn "do not run this script directly, see pbs_start_ray_cluster.sh instead"; exit 1; }
+
+# This sets up the PBS commands like 'module' which we need below.
+source /etc/bashrc
+
+ulimit -s unlimited
+ulimit -n 65535
+USER_CFG=$PBS_O_WORKDIR/.cfg_${PBS_JOBID}
+HOSTNAME=`hostname`
+JOBDIR=$PBS_JOBFS
+cd $JOBDIR
+
+NCPUS=`cat ${USER_CFG}/ncpus`
+NGPUS=`cat ${USER_CFG}/ngpus`
+IP_HEAD=`cat ${USER_CFG}/ip_head`
+
+module restore  ${USER_CFG}/module_coll >& ${USER_CFG}/worker.${HOSTNAME}.log
+module prepend-path PATH "$HOME/.local/bin"
+echo "$SCRIPTNAME: starting worker $IP_HEAD with ${NCPUS} CPUs and ${NGPUS} GPUs" >> ${USER_CFG}/worker.${HOSTNAME}.log
+ray start --address=$IP_HEAD  --num-cpus ${NCPUS} --num-gpus ${NGPUS} --block  &>> ${USER_CFG}/worker.${HOSTNAME}.log