On Mon, Mar 6, 2017 at 5:19 PM, Andres Freund <and...@anarazel.de> wrote: > The whole performance issue trigger this thread only exists when the > hashtable sizes are mis-estimated, right? Turns out that after applying > the just-committed changes, that "fixing" the bad-mixing and/or doing > iteration that's not entirely in hash-order, slighty degrades > performance. The difference is that without either of those additional > changes, we resize to the "right" size very early, when the hashtable is > barely filled (i.e. only few entries need to be moved), because the > imbalance is observed at tsart. With the changes however the resizing > happens when the table is pretty full (i.e. a lot of entries need to be > moved). So the early imbalance ends up actually not hurting > performance...
Hmm. I don't know what to do about that. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
