I can't find so far any relevant detail which could help to fix the issue.
The package versions used for Queens is oslo.cache 1.28 and for Rocky oslo.cache 1.30 I did not find any relevant changes. On Bionic we ship python-memcache 1.57.
I may need try to reproduce the issue locally since it's not clear for me why commenting [0] is fixing the it.
Did you try to restart the service without to comment line 48? also if you have a chance to clean all *.pyc from /usr/lib/python3/dist-packages/oslo_cache/ then restart the service (again without commenting anything).
I can't find so far any relevant detail which could help to fix the issue.
The package versions used for Queens is oslo.cache 1.28 and for Rocky oslo.cache 1.30 I did not find any relevant changes. On Bionic we ship python-memcache 1.57.
I may need try to reproduce the issue locally since it's not clear for me why commenting [0] is fixing the it.
Did you try to restart the service without to comment line 48? also if you have a chance to clean all *.pyc from /usr/lib/ python3/ dist-packages/ oslo_cache/ then restart the service (again without commenting anything).
In the meantime I'm continuing my investigation.
[0] https:/ /github. com/openstack/ oslo.cache/ blob/master/ oslo_cache/ _memcache_ pool.py# L48