"Joshua D. Drake" <jd@commandprompt.com> writes:
> Why are you running a vacuum every 45 seconds? Increase your fsm_pages and
> run it every hour.
If I understood his description correctly, he's turning over 10% of a
500-row table every minute. So waiting an hour would mean 3000 dead
rows in a 500-live-row table, which seems excessive. I'd agree with
running a vacuum on this specific table every five minutes or so.
Given that he is doing more than enough vacuums, I think that the
problem is probably not table bloat, but index bloat (ie, from a
constantly shifting range of live index keys, which pre-7.4 btrees
didn't handle well at all). This is just speculation though, without
proof as yet.
regards, tom lane