Re: [PERFORM] how to plan for vacuum?

On Thu, Jan 25, 2007 at 12:52:02AM -0300, Alvaro Herrera wrote:
> Jim C. Nasby wrote:
>
> > I'll generally start with a cost delay of 20ms and adjust based on IO
> > utilization.
>
> I've been considering set a default autovacuum cost delay to 10ms; does
> this sound reasonable?

For a lightly loaded system, sure. For a heavier load that might be too
much, but of course that's very dependent on not only your hardware, but
how much you want vacuum to interfere with normal operations. Though,
I'd say as a default it's probably better to be more aggressive rather
than less.

Also, it might be better to only set autovac_cost_delay by default;
presumably if someone's running vacuum by hand they want it done pronto.
--
Jim Nasby                                            jim@nasby.net
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