Re: Add two missing tests in 035_standby_logical_decoding.pl

On Mon, Apr 24, 2023 at 11:54 AM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
>
> On Mon, Apr 24, 2023 at 11:24 AM Drouvot, Bertrand
> <bertranddrouvot(dot)pg(at)gmail(dot)com> wrote:
> >
>
> Few comments:
> ============
>

+# We can not test if the WAL file still exists immediately.
+# We need to let some time to the standby to actually "remove" it.
+my $i = 0;
+while (1)
+{
+ last if !-f $standby_walfile;
+ if ($i++ == 10 * $default_timeout)
+ {
+ die
+ "could not determine if WAL file has been retained or not, can't continue";
+ }
+ usleep(100_000);
+}

Is this adhoc wait required because we can't guarantee that the
checkpoint is complete on standby even after using wait_for_catchup?
Is there a guarantee that it can never fail on some slower machines?

BTW, for the second test is it necessary that we first ensure that the
WAL file has not been retained on the primary?

--
With Regards,
Amit Kapila.