Re: pgsql: Track last_inactive_time in pg_replication_slots.

On Mon, Mar 25, 2024 at 9:54 PM Bertrand Drouvot
<bertranddrouvot.pg@gmail.com> wrote:
>
> Hi,
>
> On Mon, Mar 25, 2024 at 07:32:11PM +0530, Amit Kapila wrote:
> > On Mon, Mar 25, 2024 at 6:57 PM Robert Haas <robertmhaas@gmail.com> wrote:
> > > And I'm suspicious that having an exception for slots being synced is
> > > a bad idea. That makes too much of a judgement about how the user will
> > > use this field. It's usually better to just expose the data, and if
> > > the user needs helps to make sense of that data, then give them that
> > > help separately.
> >
> > The reason we didn't set this for sync slots is that they won't be
> > usable (one can't use them to decode WAL) unless standby is promoted
> > [2]. But I see your point as well. So, I have copied the others
> > involved in this discussion to see what they think.
>
> Yeah I also see Robert's point. If we also sync the "last inactive time" field then
> we would need to take care of the corner case mentioned by Shveta in [1] during
> promotion.

I have suggested one potential solution for that in [1]. Please have a look.

[1]:
https://www.postgresql.org/message-id/CAJpy0uB-yE%2BRiw7JQ4hW0%2BigJxvPc%2Brq%2B9c7WyTa1Jz7%2B2gAiA%40mail.gmail.com

thanks
Shveta