On Mon, Jan 9, 2017 at 8:45 AM, Edmundo Robles <edmu...@sw-argos.com> wrote:
> I have running Postgresql 9.4 and... if i have a table with following > configuration: > autovacuum_vacuum_scale_factor=0.0, > autovacuum_analyze_scale_factor=0.0, > autovacuum_vacuum_threshold=1000, > autovacuum_analyze_threshold=1000, > autovacuum_enabled=true > > Why autovacuum is not started if the table has more than 1000 inserts??? > Inserts do not generate obsolete tuples, and so are not counted against the "vacuum threshold" as described here: https://www.postgresql.org/docs/9.4/static/routine-vacuuming.html. But inserts can change the data distributions, so do count against "analyze threshold". Due to index-only-scans and freeze maps, there are reasons to revisit this topic, so that insert only tables do get vacuumed and not just analyzed. But that re-think has yet to be finished, and certainly won't be back-ported to 9.4. Cheers, Jeff