The OP is using:
autovacuum_vacuum_threshold | 100000
That means that vacuum won't consider a table to be 'vacuum-able' until after 100k changes.... that's nowhere near aggressive enough. Probably what's happening is that when autovacuum finally DOES start on a table, it just takes forever.
--Scott
2010/4/9 Merlin Moncure
<mmoncure@gmail.com> 2010/4/9 Greg Smith <greg@2ndquadrant.com>:
> Merlin Moncure wrote:
>>
>> postgresql 8.2: autovacuum enabled by default
>> postgresql 8.3: HOT (reduces update penalty -- zabbix does a lot of
>> updates)
>>
>
> autovacuum wasn't enabled by default until 8.3. It didn't really work all
> that well out of the box until the support for multiple workers was added in
> that version, along with some tweaking to its default parameters. There's
> also a lot more logging information available, both the server logs and the
> statistics tables, to watch what it's doing that were added in 8.3.
you're right! iirc it was changed at the last minute...
merlin