Date: Fri, 13 Mar 2020 19:10:00 -0500
From: Justin Pryzby <pryzby@telsasoft.com>
To: Andres Freund <andres@anarazel.de>
Cc: David Rowley <dgrowleyml@gmail.com>,
	Laurenz Albe <laurenz.albe@cybertec.at>,
	Tomas Vondra <tomas.vondra@2ndquadrant.com>,
	Amit Kapila <amit.kapila16@gmail.com>,
	Masahiko Sawada <sawada.mshk@gmail.com>,
	Darafei =?utf-8?Q?Kom=D1=8Fpa?= Praliaskouski <me@komzpa.net>,
	pgsql-hackers@lists.postgresql.org,
	Alvaro Herrera <alvherre@2ndquadrant.com>,
	Michael Banck <mbanck@gmx.net>
Subject: Re: Berserk Autovacuum (let's save next Mandrill)
Message-ID: <20200314001000.GT29065@telsasoft.com>
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On Fri, Mar 13, 2020 at 02:38:51PM -0700, Andres Freund wrote:
> > |One disadvantage of decreasing vacuum_freeze_min_age is that it might cause
> > |VACUUM to do useless work: freezing a row version is a waste of time if the row
> > |is modified soon thereafter (causing it to acquire a new XID). So the setting
> > |should be large enough that rows are not frozen until they are unlikely to
> > |change any more.
> 
> I think the overhead here might be a bit overstated. Once a page is

Could you clarify if you mean the language in docs in general or specifically
in the context of this patch ?

-- 
Justin