Earlier quoted context omitted.
Filesystem snapshot for database is not different than database crash. Databases are designed to handle crashes well (WAL etc.).
Unfortunately, this is not true. You need to grab all the DB files (WAL, etc.) in a consistent manner. You can't grab them while writes are in progress. There are ways though. Look at what Kanister does with its recipes to get consistent DB snapshots to get a sense of the complexities need to do it "right."
Perhaps you could be more specific, because the former is exactly what a filesystem snapshot is meant to do, and the latter is exactly what an ACID database is meant to allow assuming the former.
> Look at what Kanister does with its recipes to get consistent DB snapshots
I looked at a few examples and they mostly seemed to involve running the usual database dump commands.