Much of what makes redis differently useful from all the other database applications out there is based on the fact that it keeps all data in RAM. If you want a

Much of what makes redis differently useful from all the other database applications out there is based on the fact that it keeps all data in RAM. If you want a database that holds some data in memory and some on disk, there are dozens to choose from. I hope that in adding disk-based storage, redis doesn't become like most of the other databases, where you pay a price for their disk-centric storage, even if you don't need or want it.