Re: BUG #15744: Replication slot peak query throwing error for wrong sequence entry for toast chunk

Hi,

On 2019-04-10 10:28:55 +0200, Peter Eisentraut wrote:
> On 2019-04-09 22:09, PG Bug reporting form wrote:
> > PostgreSQL version: 9.6.3
>
> This is very old. 9.6.12 is current.

Right, there were a number of fixes.

> > Behavior reported (Bug)
> > We have a replication slot running for successfully but recently we
> > encountered following error:
> >
> > error: got sequence entry 2 for toast chunk 30954054 instead of seq 0
>
> > Temporary resolution
> > After running the query 2-3 times, the error went away. But this causes
> > the whole process to shut down.
> >
> > Is there any permanent resolution for the issue or is it resolved in the
> > higher version of postgres?
>
> I've not seen this particular error, but there are a number of fixes
> related to possible TOAST corruption, so this might be related to that.
> Upgrading would certainly be the first step before investigating further.

Indeed. We really would need to have a reproducible example to debug
this easily. Alternatively inspect (via you) the WAL and see exactly
what's happening. But there's not much point before you upgrade and
reproduce with a newer version.

Greetings,

Andres Freund