On Thu, Oct 6, 2016 at 8:40 PM, Jeff Janes <jeff.ja...@gmail.com> wrote: > In commit 37484ad2aacef5ec7, you changed the way that frozen tuples were > represented, so that we could make freezing more aggressive without losing > forensic evidence. But I don't think we ever did anything to actually make > the freezing more aggressive.
See 3cff1879f8d03cb729368722ca823a4bf74c0cac. The objection to doing it in other cases is that it adds write-ahead log volume which might cause its own share of problems. There might be some way of getting ahead of that, though. I think if we piggyback on an existing WAL record like XLOG_HEAP2_CLEAN or XLOG_HEAP2_VISIBLE the impact might be minimal, but I haven't been dedicated enough to try to write the patch. > When I applied the up-thread patch so that pgbench_history gets autovac, > those autovacs don't actually cause any pages to get frozen until the wrap > around kicks in, even when all the tuples on the early pages should be well > beyond vacuum_freeze_min_age. If the pages are already all-visible, they'll be skipped until vacuum_freeze_table_age is reached. -- 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
