On Wed, Apr 30, 2014 at 10:11 AM, Robert Haas <robertmh...@gmail.com> wrote: > I thought the theoretical advantage of hash indexes wasn't that they > were smaller but that you avoided a central contention point (the > btree root).
The B-Tree root isn't really a central contention point at all. The locking/latching protocol that nbtree uses is remarkably concurrency-friendly. In the real world, there is pretty much no exclusive locking of the root page's buffer. > Of course our current hash indexes have *more* not less contention > than btree but I'm pretty comfortable chalking that up to quality of > implementation rather than anything intrinsic. I am not convinced of that. -- Peter Geoghegan -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
