Re: Logical replication halted due to "this slot has been invalidated because it exceeded the maximum reserved size."

On 2022-Nov-29, Viljo Hakala wrote:

> We have two  PostgreSQL 14.3 on Red Hat Linux 8.5 running two
> different databases on VMS, where logical replicationn is used between
> databases.

Hmm, I don't see any bug fixes in the commit that would match this.
I only looked after May 9th 2022, which is 14.3's tag date.

> 2022-11-29 10:21:06.940 EET [1698404] ERROR:  could not start WAL streaming: ERROR:  cannot read from logical
replicationslot ”logs”
 
>         DETAIL:  This slot has been invalidated because it exceeded the maximum reserved size.
> 2022-11-29 10:21:06.942 EET [1698368] LOG:  background worker "logical replication worker" (PID 1698404) exited with
exitcode 1
 
> 
> Even though according to manual the max_slot_wal_keep_size is -1 and should not have a limit ?

You should see earlier messages about the slot being invalidated, during
the previous checkpoint -- and potentially the walsender being
signalled, if it was running.  Can you spot those?

> postgres=# show max_slot_wal_keep_size;
> 
>  max_slot_wal_keep_size
> ------------------------
>  -1

The only explanation of this behavior that doesn't involve a bug is that
this parameter was set to a nonzero value, then set to disabled, but the
checkpointer failed to notice the change.

-- 
Álvaro Herrera        Breisgau, Deutschland  —  https://www.EnterpriseDB.com/
"This is what I like so much about PostgreSQL.  Most of the surprises
are of the "oh wow!  That's cool" Not the "oh shit!" kind.  :)"
Scott Marlowe, http://archives.postgresql.org/pgsql-admin/2008-10/msg00152.php