alt Hacker NewsMany years ago I was obsessed with Berkeley DB and its performance.
But when I discovered Tokyo Cabinet and Tokyo Tyrant I almost literally fell in love. We used it for things that would have been impossible without it at the time.
Still worth checking it out: https://github.com/hthetiot/Tokyo-Cabinet
I got similar experience. Using Berkeley DB until I found SQLite ;) Of course it is not directly key/value, but small size, simplicity and IO performance was amazing for me.