On Fri, Jul 14, 2017 at 6:20 PM, Peter Geoghegan <pg(at)bowt(dot)ie> wrote:
> With the additional enhancements made to Postgres 10, I doubt that
> there are any remaining cases where it wins.
The thing to do about that would be to come up with some cases where
someone might plausibly think it would win and benchmark them to find
out what happens. I find it really hard to believe that sorting a
long presorted stream of tuples (or, say, 2-1-4-3-6-5-8-7-10-9 etc.)
is ever going to be as fast with any other algorithm as it is with
replacement selection.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company