Re: Add two missing tests in 035_standby_logical_decoding.pl

On Fri, May 5, 2023 at 2:59 PM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
>
> On Fri, May 5, 2023 at 1:16 PM Drouvot, Bertrand
> <bertranddrouvot(dot)pg(at)gmail(dot)com> wrote:
> >
> >
> > After multiple attempts, I got one failing one.
> >
> > Issue is that we expect this file to be removed:
> >
> > [07:24:27.261](0.899s) #WAL file is /Users/admin/pgsql/build/testrun/recovery/035_standby_logical_decoding/data/t_035_standby_logical_decoding_standby_data/pgdata/pg_wal/000000010000000000000003
> >
> > But the standby emits:
> >
> > 2023-05-05 07:24:27.216 UTC [17909][client backend] [035_standby_logical_decoding.pl][3/6:0] LOG: statement: checkpoint;
> > 2023-05-05 07:24:27.216 UTC [17745][checkpointer] LOG: restartpoint starting: immediate wait
> > 2023-05-05 07:24:27.259 UTC [17745][checkpointer] LOG: attempting to remove WAL segments older than log file 000000000000000000000002
> >
> > So it seems the test is not right (missing activity??), not sure why yet.
> >
>
> Can you try to print the value returned by
> XLogGetReplicationSlotMinimumLSN() in KeepLogSeg() on standby? Also,
> please try to print "attempting to remove WAL segments ..." on the
> primary. We can see, if by any chance some slot is holding us to
> remove the required WAL file.
>

We can also probably check the values of 'endptr', 'receivePtr', and
replayPtr on standby in the below code:

CreateRestartPoint()
{
...
/*
* Retreat _logSegNo using the current end of xlog replayed or received,
* whichever is later.
*/
receivePtr = GetWalRcvFlushRecPtr(NULL, NULL);
replayPtr = GetXLogReplayRecPtr(&replayTLI);
endptr = (receivePtr < replayPtr) ? replayPtr : receivePtr;
KeepLogSeg(endptr, &_logSegNo);
...
}

--
With Regards,
Amit Kapila.