Re: pg_receivewal documentation

On Wed, 2019-07-17 at 13:59 -0400, Jesper Pedersen wrote:
> +       <para>
> +        Note that while WAL will be flushed with this setting,
> +        <application>pg_receivewal</application> never applies it, so
> +        <xref linkend="guc-synchronous-commit"/> must not be set to
> +        <literal>remote_apply</literal> or <literal>on</literal>
> +        if <application>pg_receivewal</application> is the only synchronous standby.
> +        Similarly, if <application>pg_receivewal</application> is part of a
> +        priority-based synchronous replication setup (<literal>FIRST</literal>),
> +        or a quorum-based setup (<literal>ANY</literal>) it won't count towards
> +        the policy specified if <xref linkend="guc-synchronous-commit"/> is
> +        set to <literal>remote_apply</literal> or <literal>on</literal>.
> +       </para>

That's factually wrong.  "on" (wait for WAL flush) works fine with
pg_receivewal, only "remote_apply" doesn't.

Ok, here's another attempt:

   Note that while WAL will be flushed with this setting,
   <application>pg_receivewal</application> never applies it, so
   <xref linkend="guc-synchronous-commit"/> must not be set to
   <literal>remote_apply</literal> if <application>pg_receivewal</application>
   is the only synchronous standby.
   Similarly, it is no use adding <application>pg_receivewal</application> to a
   priority-based (<literal>FIRST</literal>) or a quorum-based
   (<literal>ANY</literal>) synchronous replication setup if
   <xref linkend="guc-synchronous-commit"/> is set to <literal>remote_apply</literal>.

Yours,
Laurenz Albe