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

On Sat, Mar 23, 2024 at 1:12 PM Bharath Rupireddy
<bharath(dot)rupireddyforpostgres(at)gmail(dot)com> wrote:
>
> On Sat, Mar 23, 2024 at 11:27 AM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
> >
>
> > 2.
> > +# Get last_inactive_time value after slot's creation. Note that the
> > slot is still
> > +# inactive unless it's used by the standby below.
> > +my $last_inactive_time_1 = $primary->safe_psql('postgres',
> > + qq(SELECT last_inactive_time FROM pg_replication_slots WHERE
> > slot_name = '$sb_slot' AND last_inactive_time IS NOT NULL;)
> > +);
> >
> > We should check $last_inactive_time_1 to be a valid value and add a
> > similar check for logical slots.
>
> That's taken care by the type cast we do, right? Isn't that enough?
>
> is( $primary->safe_psql(
> 'postgres',
> qq[SELECT last_inactive_time >
> '$last_inactive_time'::timestamptz FROM pg_replication_slots WHERE
> slot_name = '$sb_slot' AND last_inactive_time IS NOT NULL;]
> ),
> 't',
> 'last inactive time for an inactive physical slot is updated correctly');
>
> For instance, setting last_inactive_time_1 to an invalid value fails
> with the following error:
>
> error running SQL: 'psql:<stdin>:1: ERROR: invalid input syntax for
> type timestamp with time zone: "foo"
> LINE 1: SELECT last_inactive_time > 'foo'::timestamptz FROM pg_repli...
>

It would be found at a later point. It would be probably better to
verify immediately after the test that fetches the last_inactive_time
value.

--
With Regards,
Amit Kapila.