Re: [Patch] change the default value of shared_buffers in postgresql.conf.sample - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: [Patch] change the default value of shared_buffers in postgresql.conf.sample
Date
Msg-id 20210818174844.GD13002@momjian.us
Whole thread Raw
In response to Re: [Patch] change the default value of shared_buffers in postgresql.conf.sample  (Magnus Hagander <magnus@hagander.net>)
Responses Re: [Patch] change the default value of shared_buffers in postgresql.conf.sample  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
On Tue, Jun 29, 2021 at 09:28:04AM +0200, Magnus Hagander wrote:
> > 1. Since initdb will replace that string, users will never see this
> > entry as-is in live databases.  So is it worth doing anything?
> 
> It's not entirely uncommon that users copy the .sample file into their
> configuration management system and then generate the real config from
> that using templates. These users will definitely see it (and
> overwrite it).
> 
> 
> > 2. The *actual*, hard-wired, default in guc.c is 1024 (8MB), not
> > either of these numbers.  So maybe the sample file ought to use
> > that instead.  Or maybe we should change that value too ... it's
> > surely as obsolete as can be.
> 
> +1 for changing this one as well. It'a always been slightly confusing,
> since it's what shows up in pg_settings. If anything I'd consider that
> an oversight when the defaults were changed back then...
> 
> 
> > On the whole this seems pretty cosmetic so I'm inclined to leave
> > it alone.  But if we were going to do anything I think that
> > adjusting both initdb.c and guc.c to use 128MB might be the
> > most appropriate thing.
> 
> It is mostly cosmetic, but it is cosmetic at a level that can cause at
> least a small amount of confusion for users, so I'm definitely +1 for
> cleaning it up.

Yes, I liked this patch from June for the reasons outlined above.  I
don't think there is any logic to why pg_settings shows 8MB and
postgresql.conf.sample has 32MB, and this has been true since PG 10.

I think the only question is whether this is a PG 15-only patch or a
patckpatch to PG 10;  I am in favor of the later.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

  If only the physical world exists, free will is an illusion.




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