From my usage, autovacuum is not a problem for slony. There are some 
vacuum done by slony itself.
But more probably if it is autovacuum, then it is probably some xid 
wraparound ?

Keep in mind that even if autovac is disabled, it will work to reset xid :

http://www.postgresql.org/docs/8.1/static/maintenance.html#VACUUM-FOR-WRAPAROUND

That was for info, I didn't saw your question in your mail :)


Martin Fandel a écrit :
> Hi,
>
> i've installed a Slony-Replication with 2 nodes. Last year, the first
> node was the primary and the second node the secondary. This year,
> I have switchover the replication. So right now the first node is 
> secondary and the second node primary.
>
> Since yesterday, the replication was working fine. But right now all
> tables are locked while slon runs a vacuum process and i have seen 
> about 500 client processes which are hanging. A workaround for me was 
> killing the slony-vacuum process periodically. After killing it, the 
> Replication works fine and all clients are stop hanging.
>
> Here are my enviroment-informations:
>
> - Slony 1.2.9
>
> - Primary (Node 2) 
>   - 4 CPU Xeon 3,6 Ghz
>   - 4GB RAM
>   - 15k disks RAID10 
>   - SLES10 
>   - PostgreSQL 8.2.5 (compiled from source)
>
> - Secondary (Node 1)
>   - 2 CPU Xeon 1,8 Ghz
>   - 4GB RAM 
>   - 10k disks RAID10
>   - OpenSuse 10.2
>   - PostgreSQL 8.1.5 (suse rpm)
>
> I've tried this for getting the slony tables disabled for pg_autovacuum:
>
>  insert into pg_catalog.pg_autovacuum (
> 	vacrelid, 
> 	enabled,
> 	vac_base_thresh, 
> 	vac_scale_factor,
> 	anl_base_thresh, 
> 	anl_scale_factor,
> 	vac_cost_delay, 
> 	vac_cost_limit,
> 	freeze_min_age,
> 	freeze_max_age
>  ) select 
> 	oid, 
> 	'f', 
> 	'5000', 
> 	'0.2', 
> 	'10000', 
> 	'0.2', 
> 	'-1', 
> 	'-1', 
> 	'0', 
> 	'0' 
>  from 
> 	pg_catalog.pg_class 
>  where 
> 	relnamespace = (select oid from pg_namespace where nspname = '_' ||
> 'isohost_cluster') and relhasindex;
>         
> Thanks!
>
> Best regards,
>
> Martin
>
> _______________________________________________
> Slony1-bugs mailing list
> Slony1-bugs at lists.slony.info
> http://lists.slony.info/mailman/listinfo/slony1-bugs
>   


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