Re: Missing LWLock protection in pgstat_reset_replslot()

Hi,

On Wed, Mar 06, 2024 at 10:24:46AM +0530, shveta malik wrote:
> On Tue, Mar 5, 2024 at 6:52 PM Bertrand Drouvot
> <bertranddrouvot(dot)pg(at)gmail(dot)com> wrote:
> Thanks. Can we try to get rid of multiple LwLockRelease in
> pgstat_reset_replslot(). Is this any better?
>
> /*
> - * Nothing to do for physical slots as we collect stats only for logical
> - * slots.
> + * Reset stats if it is a logical slot. Nothing to do for physical slots
> + * as we collect stats only for logical slots.
> */
> - if (SlotIsPhysical(slot))
> - {
> - LWLockRelease(ReplicationSlotControlLock);
> - return;
> - }
> -
> - /* reset this one entry */
> - pgstat_reset(PGSTAT_KIND_REPLSLOT, InvalidOid,
> - ReplicationSlotIndex(slot));
> + if (SlotIsLogical(slot))
> + pgstat_reset(PGSTAT_KIND_REPLSLOT, InvalidOid,
> + ReplicationSlotIndex(slot));
>
> LWLockRelease(ReplicationSlotControlLock);
>

Yeah, it's easier to read and probably reduce the pgstat_replslot.o object file
size a bit for non optimized build.

> Something similar in pgstat_fetch_replslot() perhaps?

Yeah, all of the above done in v3 attached.

Regards,

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