The buffer pool, concurrency control, and recovery algorithm all need to dovetail into each other. In theory you could have a generic pool library that offers a

The buffer pool, concurrency control, and recovery algorithm all need to dovetail into each other. In theory you could have a generic pool library that offers a Pin and Unpin based API, but as you start talking about stuff like garbage collection that has to play nice with incremental checkpointing and the WAL rollover and... it gets hard to make a reusable library vs just each database writing something narrowly tailored to their needs. Also, a lot of the interesting research stuff going on right now is on storage engines that look fairly different from a traditional RDBMS buffer pool centric storage engine.