Re: Introduce XID age and inactive timeout based replication slot invalidation

On Sat, Mar 16, 2024 at 3:55 PM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
>
> procArray->replication_slot_catalog_xmin) but then don't adjust it for
> 'max_slot_xid_age'. I could be missing something in this but it is
> better to keep discussing this and try to move with another parameter
> 'inactive_replication_slot_timeout' which according to me can be kept
> at slot level instead of a GUC but OTOH we need to see the arguments
> on both side and then decide which makes more sense.

Hm. Are you suggesting inactive_timeout to be a slot level parameter
similar to 'failover' property added recently by
c393308b69d229b664391ac583b9e07418d411b6 and
73292404370c9900a96e2bebdc7144f7010339cf? With this approach, one can
set inactive_timeout while creating the slot either via
pg_create_physical_replication_slot() or
pg_create_logical_replication_slot() or CREATE_REPLICATION_SLOT or
ALTER_REPLICATION_SLOT command, and postgres tracks the
last_inactive_at for every slot based on which the slot gets
invalidated. If this understanding is right, I can go ahead and work
towards it.

Alternatively, we can go the route of making GUC a list of key-value
pairs of {slot_name, inactive_timeout}, but this kind of GUC for
setting slot level parameters is going to be the first of its kind, so
I'd prefer the above approach.

Thoughts?

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