On Mon, Feb 06, 2006 at 10:14:53PM -0800, Christopher Browne wrote: > > On Wed, Feb 01, 2006 at 04:37:07PM -0500, Matthew T. O'Connor wrote: > >> I think the default settings should be designed to minimize the impact > >> autovacuum has on the system while preventing the system from ever > >> getting wildly bloated (also protect xid wraparound, but that doesn't > >> have anything to do with the thresholds). > > > > I don't really see the logic behind that. Problems caused by inadequate > > vacuuming seem to be much more prevalent than problems caused by vacuum > > impacting the system. If vacuum impact is a concern I think it more > > reasonable to make the default vacuum_cost_delay non-zero instead. > > That's a good point. > > I would not be keen, on the other hand, on having the delays terribly > high. > > Big tables, if delayed significantly, will take plenty longer to > vacuum, and I always get paranoid about long running transactions :-). Very true, but I'd hope anyone running a table large enough for this to make a difference would have done some tuning of their own... What we really need is a replacement for vacuum_delay that takes PostgreSQL generated IO activity into account... -- Jim C. Nasby, Sr. Engineering Consultant jnasby@xxxxxxxxxxxxx Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461
