In Kubernetes, deploying 10 containers takes a minute or two. I haven't worked with incredibly large deployments, but really deploying any amount of containers could easily take a minute or two if you have enough nodes. There is no downtime. Database inconsistency can cause problems but also any problems like that can be mitigated by doing a two-phase change to the database, and such changes are pretty rare and also devs instinctively avoid making those kinds of schema changes.