Comment 6 for bug 1823740

This must not be a dup, or that's not the full story, because we're still seeing the symptoms of this bug with the fixed oslo cache package where we no longer see the traceback.

Here is an updated crashdump:
http://people.canonical.com/~jhobbs/juju-crashdump-openstack-2019-04-11-00.51.42.tar.gz