Date: Fri, 13 Mar 2020 07:00:56 -0500
From: Justin Pryzby <pryzby@telsasoft.com>
To: David Rowley <dgrowleyml@gmail.com>
Cc: Laurenz Albe <laurenz.albe@cybertec.at>,
	Masahiko Sawada <masahiko.sawada@2ndquadrant.com>,
	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>,
	Andres Freund <andres@anarazel.de>,
	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: <20200313120056.GK29065@telsasoft.com>
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On Wed, Mar 11, 2020 at 10:32:47AM +1300, David Rowley wrote:
> 2. The new feature can be completely disabled. This might be very
> useful for people who suffer from auto-vacuum starvation.

On Thu, Mar 12, 2020 at 08:28:05PM +1300, David Rowley wrote:
> Yes, but in particular so it can be completely disabled easily.

How is it disabled ?  By setting scale_factor=100 ?

+               {                                                                                                                                                                      
+                       "autovacuum_vacuum_insert_scale_factor",                                                                                                                       
+                       "Number of tuple inserts prior to vacuum as a fraction of reltuples",                                                                                          
+                       RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,                                                                                                                          
+                       ShareUpdateExclusiveLock                                                                                                                                       
+               },                                                                                                                                                                     
+               -1, 0.0, 100.0                                                                                                                                                         

Note, vacuum_cleanup_index_scale_factor uses max: 1e10
See 4d54543efa5eb074ead4d0fadb2af4161c943044

-- 
Justin