Performance data for LevelDB, Berkley DB and BangDB for Random Operations (highscalability.com)

OpenLDAP's MDB is also in this space that is new enough that most people haven't heard of it's exitence.

http://www.symas.com/mdb/

Looking at the benchmarks, something looks wrong in the graphs. For example, for one it looks like they were doing from 0-2M ops for the test. Some of the engines were claimed to do 1M ops per second. That would result in a 2 second benchmark?

Is a 2 second benchmark actually useful?