Peter Geoghegan <p...@heroku.com> writes: > I think that we *can* refine this guess, and should, because random > I/O is really quite unlikely to be a large cost these days (I/O in > general often isn't a large cost, actually). More fundamentally, I > think it's a problem that cost_sort() thinks that external sorts are > far more expensive than internal sorts in general. There is good > reason to think that that does not reflect the reality. I think we can > expect external sorts to be *faster* than internal sorts with > increasing regularity in Postgres 10.
TBH, if that's true, haven't you broken something? regards, tom lane -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers