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

On Fri, Jul 15, 2022 at 09:29:20PM +0800, Japin Li wrote:
>
> On Fri, 15 Jul 2022 at 08:49, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
> > On Tue, Jul 5, 2022 at 08:02:33PM -0400, Tom Lane wrote:
> >> "Precondition" is an overly fancy word that makes things less clear
> >> not more so. Does it mean that setting wal_level = minimal will fail
> >> if you don't do these other things, or does it just mean that you
> >> won't be getting the absolute minimum WAL volume? If the former,
> >> I think it'd be better to say something like "To set wal_level to minimal,
> >> you must also set [these variables], which has the effect of disabling
> >> both WAL archiving and streaming replication."
> >
> > I have created the attached patch to try to improve this text.
>
> IMO we can add the following sentence for wal_level description, since
> if wal_level = minimal and max_wal_senders > 0, we cannot start the database.
>
> To set wal_level to minimal, you must also set max_wal_senders to 0,
> which has the effect of disabling both WAL archiving and streaming
> replication.

Okay, text added in the attached patch.

--
Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EDB https://enterprisedb.com

Indecision is a decision. Inaction is an action. Mark Batterson