db4o now offers a new statistics module. Statistics can be turned on for various layers within the database and visualized using your favorite JMX enabled tooling. Developers can use these to asses the quality of their design choices and look for ways to tune by adding indexes and more. Available stats deal with layers including: caching, low level I/O, network, queries, etc. You can learn more about this new module in the db4o developer community blog Got objects? Try an object database and lose the mapping blues. The db4o team Versant - The database for developers