Date: Sat, 28 Mar 2020 10:49:02 -0300
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Cc: Masahiko Sawada <masahiko.sawada@2ndquadrant.com>,
	Sergei Kornilov <sk@zsrv.org>,
	Michael Paquier <michael@paquier.xyz>,
	pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: base backup client as auxiliary backend process
Message-ID: <20200328134902.GA11688@alvherre.pgsql>
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On 2020-Jan-14, Peter Eisentraut wrote:

> On 2020-01-14 07:32, Masahiko Sawada wrote:
> > -     <entry>Replication slot name used by this WAL receiver</entry>
> > +     <entry>
> > +      Replication slot name used by this WAL receiver.  This is only set if a
> > +      permanent replication slot is set using <xref
> > +      linkend="guc-primary-slot-name"/>.  Otherwise, the WAL receiver may use
> > +      a temporary replication slot (determined by <xref
> > +      linkend="guc-wal-receiver-create-temp-slot"/>), but these are not shown
> > +      here.
> > +     </entry>
> > 
> > Now that the slot name is shown even if it's a temp slot the above
> > documentation changes needs to be changed. Other changes look good to
> > me.
> 
> committed, thanks

Sergei has just proposed a change in semantics: if primary_slot_name is
specified as well as wal_receiver_create_temp_slot, then a temp slot is
used and it uses the specified name, instead of ignoring the temp-slot
option as currently.

Patch is at https://postgr.es/m/3109511585392143@myt6-887fb48a9c29.qloud-c.yandex.net

(To clarify: the current semantics if both options are set is that an
existing permanent slot is sought with the given name, and an error is
raised if it doesn't exist.)

What do you think?  Preliminarly I think the proposed semantics are
saner.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services