Comment 2 for bug 1644154

I think this is related to bug 1664025 where the unit is bootstrapped using the bootstrap-pxc action, but ends up in the wrong cgroup and can be shutdown and not restarted if the juju unit agent is restarted for some reason (a juju upgrade-juju operation for example).

This has just been fixed into the stable percona-cluster charm, so this should now be resolved.