unexpected pod restart during high memory pressure

Configured machine only has 10GB of RAM; after cluster bootstrap memory utilisation was at 85%; configure command executed during which (after image was uploaded) all of the pods in the microk8s deployment restarted.

A few issues

a) why did the pods get restarted
b) mysql did restart and recovered but no mysql-router instances where able to reconnect to the backend database:

2023-06-06 10:23:45 metadata_cache INFO [7feee411b640] Starting metadata cache refresh thread
2023-06-06 10:23:45 metadata_cache WARNING [7feee411b640] Failed connecting with Metadata Server mysql-0.mysql-endpoints.openstack.svc.cluster.local:3306: Access denied for user 'mysql_router1_159cr99xjlpp'@'keystone-mysql-router-0.keystone-mysql-router-endpoints.openstac' (using password: YES) (1045)
2023-06-06 10:23:45 metadata_cache ERROR [7feee411b640] Failed fetching metadata from any of the 1 metadata servers.
2023-06-06 10:23:45 routing INFO [7feeb1ffb640] [routing:bootstrap_ro] started: routing strategy = round-robin-with-fallback