On Tue, Mar 12, 2019 at 2:34 PM Peter Geoghegan <p...@bowt.ie> wrote: > On Tue, Mar 12, 2019 at 11:32 AM Robert Haas <robertmh...@gmail.com> wrote: > > If I wanted to try to say this in fewer words, would it be fair to say > > that reducing the size of an index by 40% without changing anything > > else can increase contention on the remaining pages? > > Yes.
Hey, I understood something today! I think it's pretty clear that we have to view that as acceptable. I mean, we could reduce contention even further by finding a way to make indexes 40% larger, but I think it's clear that nobody wants that. Now, maybe in the future we'll want to work on other techniques for reducing contention, but I don't think we should make that the problem of this patch, especially because the regressions are small and go away after a few hours of heavy use. We should optimize for the case where the user intends to keep the database around for years, not hours. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company