RE: speed up a logical replica setup

Dear Amit,

> Your analysis looks correct to me. The test could fail due to
> autovacuum. See the following comment in
> 040_standby_failover_slots_sync.
>
> # Disable autovacuum to avoid generating xid during stats update as otherwise
> # the new XID could then be replicated to standby at some random point making
> # slots at primary lag behind standby during slot sync.
> $publisher->append_conf('postgresql.conf', 'autovacuum = off');
>

Oh, I could not find the comment. I felt it should be added even in
040_pg_createsubscriber.pl. Done.

> > # Descriptions for attached files
> >
> > An attached script can be used to reproduce the first failure without
> pg_createsubscriber.
> > It requires to modify the code like [1].
>
> > 0003 patch disables autovacuum for node_p and node_s. I think node_p is
> enough, but did
> > like that just in case. This fixes a second failure.
> >
>
> Disabling on the primary node should be sufficient. Let's do the
> minimum required to stabilize this test.

+1, removed.

PSA new version. 0001 has not been changed yet. A comment was added
in 0002 to clarify why we must wait. For 0003, a comment was added and
setting for standby was reverted.

Best Regards,
Hayato Kuroda
FUJITSU LIMITED
https://www.fujitsu.com/