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From: Xuneng Zhou <xunengzhou@gmail.com>
Date: Sat, 23 May 2026 20:51:40 -0700
Message-ID: 
 <CABPTF7VSX4b29unitKHN-dtiTy6hx3nvLsirUBNA=opOhnv+Mg@mail.gmail.com>
Subject: Re: Fix pg_stat_wal_receiver to show CONNECTING status
To: Chao Li <li.evan.chao@gmail.com>, Michael Paquier <michael@paquier.xyz>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>,
	Michael Paquier <michael.paquier@gmail.com>
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On Sat, May 23, 2026 at 8:51=E2=80=AFAM Xuneng Zhou <xunengzhou@gmail.com> =
wrote:
>
> On Fri, May 22, 2026 at 4:56=E2=80=AFPM Chao Li <li.evan.chao@gmail.com> =
wrote:
> >
> >
> >
> > > On May 23, 2026, at 07:23, Michael Paquier <michael@paquier.xyz> wrot=
e:
> > >
> > > On Fri, May 22, 2026 at 10:06:33AM +0800, Chao Li wrote:
> > >> Here comes the patch set:
> > >>
> > >> * v3-0001 is the exactly same as v2-0001
> > >> * In v3-0002, the change in walreceiverfuncs.c is the same as the
> > >> * previous diff, and I tuned the test change a little bit.
> > >
> > > Okay, applied the first one on HEAD, and backpatched the second one.
> > > --
> > > Michael
> >
> > Thank you very much for applying the patch and still working hard durin=
g the PGConf.
> >
>
>
> Thanks for dealing with this and sorry for being late in the game.
> I'll do a post-commit review while I'm on the flight.


I agree with Michael's point that displaying partial columns gated by
the flag ready-to-display is not very ideal. Showing two columns in
connecting status inconsistently in some scenarios implies something
broken under the hood.[1] It may require extra documentation effort to
dispel the confusion for the user.

As for the timeline/lsn and timestamp values, they may still be useful
operationally because they reveal when the WAL receiver entered this
part of the code. Although they are not meant to be used and
interpreted in this way... So there's some risk for misinterpretation,
but they precedes the changes.

[1] https://www.postgresql.org/message-id/aaj_WA1Du4micf9t@paquier.xyz


--
Regards,
Xuneng Zhou
HighGo Software Co., Ltd.