Re: Vacuum Cost Documentation?

Jan Wieck wrote:
> On 8/6/2004 11:34 PM, Bruce Momjian wrote:
>
> > Jan Wieck wrote:
> >> On 8/6/2004 9:04 PM, Bruce Momjian wrote:
> >>
> >> > Updated. Thanks.
> >>
> >> I thought we want to have the feature activated ... I reversed your
> >> change and brought guc.c in sync instead.
> >
> > Uh, if the guy is doing a vacuum at night, does he want the delay?
> > Seems someone should have to enable the delay by default, or does your
> > setup recoginize when it is being run on a lightly loaded system?
> >
> >
>
> Those people will instantly realize what is going on and either change
> the delay setting or start running vacuum at daytime too.
>
> What this buys us is that over time we will see less researches and
> articles telling people that you have to bring down a PostgreSQL DB
> frequently for vacuum maintenance because those "testers" run their fair
> comparisions with out of the box configuration settings.

I am not in favor of adding a delay in VACUUM unless people ask for it.
Imagine either night vacuum or a vacuum you run in your application
after you delete and just before you load a table. Neither want a
vacuum. I think people who want a delay will think to ask for it while
people who want a quick vacuum will just think that vacuum is slow.

--
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