Date: Wed, 28 Dec 2022 19:23:54 -0600
From: Justin Pryzby <pryzby@telsasoft.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Peter Geoghegan <pg@bowt.ie>, postgresql@taljaren.se,
	pgsql-hackers@lists.postgresql.org,
	Michael Paquier <michael@paquier.xyz>
Subject: Re: BUG #17717: Regression in vacuumdb (15 is slower than 10/11 and
 possible memory issue)
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On Wed, Dec 28, 2022 at 03:13:23PM -0500, Tom Lane wrote:
> Peter Geoghegan <pg@bowt.ie> writes:
> > On Fri, Dec 16, 2022 at 6:49 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> >> That is a really good point.  How about teaching VACUUM to track
> >> the oldest original relfrozenxid and relminmxid among the table(s)
> >> it processed, and skip vac_update_datfrozenxid unless at least one
> >> of those matches the database's values?  For extra credit, also
> >> skip if we didn't successfully advance the source rel's value.
> 
> > Hmm. I think that that would probably work.
> 
> I'm forced to the conclusion that we have to expose some VACUUM
> options if we want this to work well.  Attached is a draft patch
> that invents SKIP_DATABASE_STATS and ONLY_DATABASE_STATS options
> (name bikeshedding welcome) and teaches vacuumdb to use them.

I was surprised to hear that this added *two* options.

I assumed it would look like:

VACUUM (UPDATE_DATABASE_STATS {yes,no,only})

-- 
Justin