Small script to launch a process in a slice/cgroup

run-in-slice.sh

#!/bin/bash
set -euo pipefail

# Drop in /usr/local/bin/run-in-slice
#
# Requires system to be running systemd and cgroupsv2

SLICE="$1"
shift

[[ "$SLICE" = *".slice" ]] || SLICE="${SLICE}.slice"

SLICE_DIR="/sys/fs/cgroup/user.slice/user-$UID.slice/user@$UID.service/$SLICE"
mkdir -p "$SLICE_DIR"
echo "Moving to $SLICE_DIR"

echo $$ > "$SLICE_DIR/cgroup.procs"
exec $@