On Wed, Apr 21, 2010 at 11:06 AM, Rick <richard.bran...@ca.com> wrote: > I have a DB with small and large tables that can go up to 15G. > For performance benefits, it appears that analyze has much less cost > than vacuum, but the same benefits?
Err, no. ANALYZE gathers statistics for the query planner; VACUUM clears out old, dead tuples so that space can be reused by the database system. > I can’t find any clear recommendations for frequencies and am > considering these parameters: > > Autovacuum_vacuum_threshold = 50000 > Autovacuum_analyze_threshold = 10000 > Autovacuum_vacuum_scale_factor = 0.01 > Autovacuum_analyze_scale_factor = 0.005 > > This appears it will result in table analyzes occurring around 10,000 > to 85,000 dead tuples and vacuum occuring around 50,000 to 200,000, > depending on the table sizes. > > Can anyone comment on whether this is the right strategy and targets > to use? I'm not that familiar with tuning these parameters but increasing the default thesholds by a thousand-fold doesn't seem like a good idea. Small tables will never get vacuumed or analyzed at all. ...Robert -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
