Date: Fri, 26 Nov 2021 14:36:25 -0300
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Cc: b1000101@pm.me, pgsql-docs@lists.postgresql.org
Subject: Re: max_slot_wal_keep_size unit is not specified
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On 2021-Nov-26, Kyotaro Horiguchi wrote:

> Regarding the proposed description, we have never explained how the
> same kind of values specified in megabytes is converted into internal
> units.  If we add that explanation there, we might want the same for
> max_wal_size, min_wal_size and wal_keep_size.

True.  Since this was for backpatch, it seemed best to copy the existing
entries instead of changing them.

> The same section starts with the following sentences.
> 
> >        Specify the maximum size of WAL files
> >        that <link linkend="streaming-replication-slots">replication
> >        slots</link> are allowed to retain in the <filename>pg_wal</filename>
> >        directory at checkpoint time.
> 
> FWIW I thought (or intended) that "the maximum size of WAL files that
> slots are *allowed to retain*" connotes the same to the sentences
> cited above.

Right you are -- that addition was redundant, so I pushed without that.

> Premising "16 MB one way or the other don't change things much", I'm
> not sure we really need to be particular about a few megabites
> difference especially only for this specific variable.

Yeah.

-- 
Álvaro Herrera              Valdivia, Chile  —  https://www.EnterpriseDB.com/