Re: Doc about how to set max_wal_senders when setting minimal wal_level

At Fri, 04 Mar 2022 12:18:29 +0800, Japin Li <japinli(at)hotmail(dot)com> wrote in
>
> On Thu, 03 Mar 2022 at 12:10, Japin Li <japinli(at)hotmail(dot)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