From the release notes of the latest monero 0.10.2 version:
added support for multiple daemons using the same LMDB database
What sensible use case should that cover? From my understanding, LMDB databases are meant to be used locally, so for what reason should multiple deamons run locally?
The use case I had in mind when I wrote this code is to run daemons on different network interfaces, or on different network protocols, using the same database. E.g., if you want to use different bandwidth limits on one interface vs another, or if you want to run a daemon on TOR simultaneously with a daemon on clearnet. Or, you want to run a public node (with --restricted-rpc) and also want to run a daemon that mines at the same time.
You can run as many daemons as you want on the same database without the DB taking up any additional memory.
