[makmanalp]

For those who don't know, Goetz Graefe is sort of the patron saint of btrees. He recently won the Sigmod Codd innovations award for his contributions:

https://sigmod.org/sigmod-awards/people/goetz-graefe-2017-si...

He also has a lot to say about locking in B-trees:

http://15721.courses.cs.cmu.edu/spring2016/papers/a16-graefe...