Re: archive modules

On Tue, Aug 23, 2022 at 04:18:52PM +0200, talk to ben wrote:
> --- a/doc/src/sgml/basic-archive.sgml
> +++ b/doc/src/sgml/basic-archive.sgml
> @@ -68,6 +68,19 @@ basic_archive.archive_directory = '/path/to/archive/directory'
>     to any archiving still in progress, but users should use extra caution when
>     doing so.
>    </para>
> +
> +  <para>
> +   The archive module is loaded by the archiver process. Therefore, the
> +   parameters defined in the module are not set outside this process and cannot
> +   be seen from the <structname>pg_settings</structname> view or the
> +   \dconfig meta-command.
> +   These parameters values can be shown from the server's configuration
> +   file(s) through the <structname>pg_file_settings</structname> view.
> +   If you want to check the actual values applied by the archiver, you can
> +   <command>LOAD</command> the module before reading
> +   <structname>pg_settings</structname>. It's also possible to search
> +   for  the options directly with the <command>SHOW</command> command.
> +  </para>

I don't know if it makes sense to document this in basic_archive.  On one
hand, it seems like folks will commonly encounter this behavior with this
module, so this feels like a natural place for such a note.  But on the
other hand, this is generic behavior for any library that is dynamically
loaded in a separate process.

Overall, I think I'm +1 for this patch.  I haven't thought too much about
the exact wording, but provided others support it as well, I will try to
take a deeper look soon.

-- 
Nathan Bossart
Amazon Web Services: https://aws.amazon.com