Zero-downtime major upgrades for Postgres
Currently, we have no well-developed procedure to have zero-downtime Postgres upgrades.
Feedback from a customer:
We were just looking into upgrading from Postgresql 14 to 15. We tried switching the config setting in the Database Lab config to use 15 for the dockerImage setting. However, when we tried to clone a DB, we got the following error: dial unix /var/lib/dblab/dblab_pool/dataset_1/sockets/dblab_clone_6016/.s.PGSQL.6016: connect: no such file or directory
It took maybe 40+ seconds trying to clone before failing with that error.
We need to develop it for both physical and logical modes, assuming that there are multiple disks/pools in use + publish a HowTo for it.