Re: Doc about how to set max_wal_senders when setting minimal wal_level - Mailing list pgsql-hackers

From Kyotaro Horiguchi
Subject Re: Doc about how to set max_wal_senders when setting minimal wal_level
Date
Msg-id 20220304.150535.1261751585521581252.horikyota.ntt@gmail.com
Whole thread Raw
In response to Re: Doc about how to set max_wal_senders when setting minimal wal_level  (Japin Li <japinli@hotmail.com>)
Responses Re: Doc about how to set max_wal_senders when setting minimal wal_level  (Japin Li <japinli@hotmail.com>)
Re: Doc about how to set max_wal_senders when setting minimal wal_level  ("David G. Johnston" <david.g.johnston@gmail.com>)
List pgsql-hackers
At Fri, 04 Mar 2022 12:18:29 +0800, Japin Li <japinli@hotmail.com> wrote in 
> 
> On Thu, 03 Mar 2022 at 12:10, Japin Li <japinli@hotmail.com> wrote:
>
> Attach v3 patch to fix missing close varname tag.

+        A precondition for using minimal WAL is to disable WAL archiving and
+        streaming replication by setting <xref linkend="guc-max-wal-senders"/>
+        to <literal>0</literal>, and <varname>archive_mode</varname>
+        to <literal>off</literal>.

It is a bit odd that the features to stop and the corresponding GUCs
are written irrespectively. It would be better they're in the same
order.

+        servers.  If setting <varname>max_wal_senders</varname> to
+        <literal>0</literal> consider also reducing the amount of WAL produced
+        by changing <varname>wal_level</varname> to <literal>minimal</literal>.

Those who anively follow this suggestion may bump into failure when
arhive_mode is on.  Thus archive_mode is also worth referred to.  But,
anyway, IMHO, it is mere a performance tips that is not necessarily
required in this section, or even in this documentaiotn.  Addtion to
that, if we write this for max_wal_senders, archive_mode will deserve
the similar tips but I think it is too verbose.  In short, I think I
would not add that description at all.

regards.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center



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