Jeff Janes <jeff.janes@xxxxxxxxx> wrote: > Amit Kapila <amit.kapila@xxxxxxxxxx> wrote: >> One of the important difference is that during the time VACUUM >> FULL is operating on a relation, no other operations will be >> allowed on that relation. Most of admin care about this point, >> because they don't want to stop operations for background >> garbage collect. > While that is true, it is not a reason not to update > pg_stat_get_last_vacuum_time. I'm having a hard time coming up > with a reason not to update pg_stat_get_last_vacuum_time with a > full vacuum. > > On version 8.4 and below, you could justify it by saying that > VACUUM FULL bloated the indexes and then left them that way, and > so we shouldn't update the time field. But that is no longer the > case. And even then, doing a ordinary vacuum afterwards isn't > going to fix the index bloat, so even that argument is a bit > sketchy. I'm not sure that what we're doing now is correct, but updating things as if a normal vacuum had been done would *not* be the thing to do. For starters, VACUUM FULL blows away the free space map and visibility map for a table. Among other things, that means that index-only scans will cease to work until the table has a normal vacuum. A normal vacuum (or autovacuum) will restore those, so a VACUUM FULL should probably set things up to show that the table is in need of a vacuum soon. -- Kevin Grittner EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
