Re: Missing LWLock protection in pgstat_reset_replslot()

Hi,

On Thu, Mar 07, 2024 at 02:17:53PM +0900, Michael Paquier wrote:
> On Wed, Mar 06, 2024 at 09:05:59AM +0000, Bertrand Drouvot wrote:
> > Yeah, all of the above done in v3 attached.
> 
> In passing..  pgstat_create_replslot() and pgstat_drop_replslot() rely
> on the assumption that the LWLock ReplicationSlotAllocationLock is
> taken while calling these routines.  Perhaps that would be worth some
> extra Assert(LWLockHeldByMeInMode()) in pgstat_replslot.c for these
> two?  Not directly related to this problem.

Yeah, good point: I'll create a dedicated patch for that.

Note that currently pgstat_drop_replslot() would not satisfy this new Assert
when being called from InvalidatePossiblyObsoleteSlot(). I think this call
should be removed and created a dedicated thread for that [1].

[1]: https://www.postgresql.org/message-id/ZermH08Eq6YydHpO%40ip-10-97-1-34.eu-west-3.compute.internal

Regards,

-- 
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
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