Legit concern. However one of the things that autovacuum is supposed to do is not vacuum tables that don't need it. This can result in an overal reduction in vacuum overhead. In addition, if you see that autovacuum is firing off vacuum commands during the day and they are impacting your response time, then you can play with the vacuum cost delay settings that are design to throttle down the IO impact vacuum commands can have. In addition if you use 8.1, you can set per table thresholds, per table vacuum cost delay settings, and autovacuum will respect the work done by non-autovacuum vacuum commands. Meaning that if you manually vacuum tables at night during a maintenance window, autovacuum will take that into account. Contrib autovacuum couldn't do this. Hope that helps. Real world feed-back is always welcome. Matt > I am concerned with the impact autovacuum of table(s) would have on > regular DB activity. > > With our current DB's the majority of tables have either a low number of > updates or a large number of inserts (which I believe should not be a > problem), however, a small number of tables have an extremely high > number of updates (up to 150 000)
