For me, personally -- I cannot think of a sufficient justification to put a production database in a container. A good database server is designed for performance, reliability, scalability, security, etc., without containers. Putting a production database inside a container introduces a world of unnecessary edge cases and complexity.
Depends on requirements. Someone needs one big, highly-optimized DB instance. Someone else needs high-availability 3+ instance cluster. Having a cluster of containers brings performance penalty but if your app is read-heavy, you can read from all instances and multiply read throughput...
Thanks for your feedback. I might run the DB on the host then, and just use containers for the app server. I'm not at the scale to warrant a separate host for the DB.
