The biggest changes for this release have happened under the hood. The new revised BTree index architecture has matured and the new query processor can now work in "lazy query evaluation mode."
In comparison to version 5.x performance can be seen to improve by up to 10x for a wide range of usecases. At the same time the memory consumption during query execution has been reduced close to zero, resulting in overall reduced memory consumption of up to 90% less for typical db4o applications.
The db4o team has documented the leap in performance using the Poleposition database benchmark.
New lazy query functionality also improves db4o for Client/Server use, since there is now full control on how query execution processing time is to be balanced between individual clients and for specific queries.
db4objects has also released new 6.0 versions of the dRS replication system and of the "ObjectManager" database browser.
All 6.0 product versions are available for free download under the GPL.