Re: Add memory_limit_hits to pg_stat_replication_slots

Hi,

On Mon, Oct 06, 2025 at 01:18:38PM -0700, Masahiko Sawada wrote:
> On Sun, Oct 5, 2025 at 11:52 PM Bertrand Drouvot
> <bertranddrouvot(dot)pg(at)gmail(dot)com> wrote:
> >
> > Could we also imagine that there are other activities enough to reach the memory
> > limit and transactions are not aborted, meaning spill_txns and/or spill_count are > 0?
> >
> > In that case we may want to get rid of this test instead (as checking spill_txns >=0
> > and spill_count >=0 would not really reflect the intend of this test).
>
> It makes sense to me to make an assumption that there are no
> concurrent activities that are capturable by logical decoding during
> this test. So I think we don't need to care about that case. On the
> other hand, under this assumption, it also makes sense to check it
> with the exact number. I've chosen >0 as we can achieve the same goal
> while being more flexible for potential future changes. I'm open to
> other suggestions though.

>0 is fine by me. I was just wondering about spill_txns and spill_count too.

That could sound weird that we are confident for spill_txns and spill_count
to rely on the exact values and not for the new field. That said, I agree that
>0 is more flexible for potential future changes (in the sense that this one
is more likely to change in its implementation). In short, I'm fine with your
proposal.

Regards,

--
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com