Re: [PATCH] Add max_logical_replication_slots GUC

Right now, all replication slots share a single global limit:
max_replication_slots.

That means logical and physical replication slots compete for the same pool.

In practice, a burst of logical replication activity can exhaust all
available
replication slots, which in turn prevents physical standbys from connecting
or restarting.

This is problematic because logical replication slots are often user-managed
and can grow dynamically, while physical replication slots are
infrastructure-critical and expected to remain available.
Best regards,

--
Ahmed Et-tanany
Aiven: https://aiven.io/

On Wed, Jan 28, 2026 at 1:28 PM Álvaro Herrera <alvherre(at)kurilemu(dot)de> wrote:

> Hello,
>
> On 2026-Jan-28, Ahmed Et-tanany wrote:
>
> > This provides a separation between logical and total replication
> > slots, and allows users to control logical slot usage independently.
>
> Hmm, why is this useful?
>
> --
> Álvaro Herrera 48°01'N 7°57'E —
> https://www.EnterpriseDB.com/
> "Thou shalt not follow the NULL pointer, for chaos and madness await
> thee at its end." (2nd Commandment for C programmers)
>

--
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*Ahmed Et-tanany*
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