OpenDJ exposes a monitoring entry for each JE database environment. It would be nice if we supported similar monitoring capabilities for our other storage engines.
From a design point of view, I don't think there needs to be any provision for monitoring in the StorageEngine API itself: I don't think the PluggableBackend needs to "know" about the underlying storage engine's monitoring capabilities. Instead, I think each storage engine implementation will be responsible for registering and publishing its own monitors.
In other words, I think a solution to this issue will not involve any StorageEngine API changes nor changes to the PluggableBackend implementation. The changes will be specific to the Persistit storage engine.