Re: New standby_slot_names GUC in PG 17

Masahiko Sawada <sawada.mshk@gmail.com>

From: Masahiko Sawada <sawada.mshk@gmail.com>
To: "Zhijie Hou (Fujitsu)" <houzj.fnst@fujitsu.com>
Cc: Amit Kapila <amit.kapila16@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, Muhammad Ikram <mmikram@gmail.com>, Bruce Momjian <bruce@momjian.us>, PostgreSQL-development <pgsql-hackers@postgresql.org>, Nathan Bossart <nathandbossart@gmail.com>
Date: 2024-06-25T02:50:14Z
Lists: pgsql-hackers
On Tue, Jun 25, 2024 at 11:21 AM Zhijie Hou (Fujitsu)
<houzj.fnst@fujitsu.com> wrote:
>
> On Saturday, June 22, 2024 5:47 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
> >
> > On Sat, Jun 22, 2024 at 1:49 AM Nathan Bossart
> > <nathandbossart@gmail.com> wrote:
> > >
> > > On Fri, Jun 21, 2024 at 03:50:00PM -0400, Tom Lane wrote:
> > > >>>>> Allow specification of physical standbys that must be
> > > >>>>> synchronized before they are visible to subscribers (Hou Zhijie,
> > > >>>>> Shveta Malik)
> > > >
> > > > it seems like the name ought to have some connection to
> > > > synchronization.  Perhaps something like "synchronized_standby_slots"?
> > >
> > > IMHO that might be a bit too close to synchronous_standby_names.
> > >
> >
> > Right, but better than the current one. The other possibility could be
> > wait_for_standby_slots.
>
> I agree the current name seems too generic and the suggested ' synchronized_standby_slots '
> is better than the current one.
>
> Some other ideas could be:
>
> synchronize_slots_on_standbys: it indicates that the standbys that enabled
> slot sync should be listed in this GUC.
>
> logical_replication_wait_slots: it means the logical replication(logical
> Walsender process) will wait for these slots to advance the confirm flush
> lsn before proceeding.

I feel that the name that has some connection to "logical replication"
also sounds good. Let me add some ideas:

- logical_replication_synchronous_standby_slots (might be too long)
- logical_replication_synchronous_slots

Regards,

-- 
Masahiko Sawada
Amazon Web Services: https://aws.amazon.com



Commits

  1. Update release notes to reflect recent commit 0f934b0739.

  2. Rename standby_slot_names to synchronized_standby_slots.

  3. Add a new slot sync worker to synchronize logical slots.