What are most of you setting your vacuum and autovacuum parameters to for your 8.x databases. I just turned on autovacuuming on one of my db servers and went with a very conservative vacuum_cost_delay of 200 and vacuum_cost_limit of 50. I am wondering if anyone else has tested to find out just how far you can push your vacuum/autovacuum before you start to feel performance hits from running it?