Re: pg_multixact issues

On Thu, Sep 18, 2014 at 2:41 AM, Adrian Klaver <adrian(dot)klaver(at)aklaver(dot)com>
wrote:

>
> Aaah, hit enter too soon. Also see the other changes under Changes that
> apply to multixact in 9.3.5

Thanks for sharing same. Found this one interesting "Truncate pg_multixact
during checkpoints, not during VACUUM (Álvaro Herrera)" and also other
changes. But am not sure are you suggesting to move to 9.3.5 ?

Actually looking for some guidelines on truncating pg_multixact at this
situation.

- Do I need to run vaccum manually here and then the pg_multixact can be
truncated?
- Actually looking out for some hints wherein can know the current
pg_multixact/members which are active and which one are stale which can be
truncated? Is there any query to find this information?

pg_class.relminmxid can be referred but should I change the value of
autovacuum_multixact_freeze_max_age which defaults to 400 million
multixacts, setting this value to lower limits would help in cleaning up
pg_multixact?

Regards...