Alvaro Herrera wrote: > > Once autovacuum_naptime... autovacuum_max_workers... > How does this sound?
The knobs exposed on autovacuum feel kinda tangential to what I think I'd really want to control. IMHO "vacuum_mbytes_per_second" would be quite a bit more intuitive than cost_delay, naptime, etc. ISTM I can relatively easily estimate and/or spec out how much "extra" I/O bandwidth I have per device for vacuum; and would pretty much want vacuum to be constantly running on whichever table that needs it the most so long as it can stay under that bandwith limit. Could vacuum have a tunable that says "X MBytes/second" (perhaps per device) and have it measure how much I/O it's actually doing and try to stay under that limit? For more fine-grained control a cron job could go around setting different MBytes/second limits during peak times vs idle times. If people are concerned about CPU intensive vacuums instead of I/O intensive ones (does anyone experience that? - another tuneable "vacuum_percent_of_cpu" would be more straightforward than delay_cost, cost_page_hit, etc. But I'd be a bit surprised if cpu intensive vacuums are common. ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
