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

On Wed, Mar 27, 2024 at 6:54 PM Bertrand Drouvot
<bertranddrouvot(dot)pg(at)gmail(dot)com> wrote:
>
> Hi,
>
> On Wed, Mar 27, 2024 at 05:55:05PM +0530, Bharath Rupireddy wrote:
> > On Wed, Mar 27, 2024 at 3:42 PM Bertrand Drouvot
> > Please see the attached v28 patch.
>
> Thanks!
>
> 1 === sorry I missed it in the previous review
>
> if (!(RecoveryInProgress() && slot->data.synced))
> + {
> now = GetCurrentTimestamp();
> + update_inactive_since = true;
> + }
> + else
> + update_inactive_since = false;
>
> I think update_inactive_since is not needed, we could rely on (now > 0) instead.

Thought of using it, but, at the expense of readability. I prefer to
use a variable instead. However, I changed the variable to be more
meaningful to is_slot_being_synced.

> 2 ===
>
> +=item $node->get_slot_inactive_since_value(self, primary, slot_name, dbname)
> +
> +Get inactive_since column value for a given replication slot validating it
> +against optional reference time.
> +
> +=cut
> +
> +sub get_slot_inactive_since_value
> +{
>
> shouldn't be "=item $node->get_slot_inactive_since_value(self, slot_name, reference_time)"
> instead?

Ugh. Changed.

> Apart from the above, LGTM.

Thanks. I'm attaching v29 patches. 0001 managing inactive_since on the
standby for sync slots. 0002 implementing inactive timeout GUC based
invalidation mechanism.

Please have a look.

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