Re: AutoVacuum Behaviour Question

Alvaro Herrera wrote:
> Bruce McAlister wrote:
>
> Ok now this is interesting:
>
>> select datname, age(datfrozenxid) from pg_database;
>> datname | age
>> -------------------------+-----------
>> blueface-crm | 441746613
>
> Note this value is 440 million, and you said in your original report that
>
>> autovacuum_freeze_max_age = 200000000
>
> 200 million. So this database is being selected each time because of
> this.
>

Ahhh okay, I didnt know how to extract the age for a database. Learnt
something new here.

> However, what should happen is that after the vacuum the age of the
> database is decreased after the vacuuming. What's your
> vacuum_freeze_min_age setting?
>

My *_freeze_* values are:

autovacuum_freeze_max_age = 200000000
#vacuum_freeze_min_age = 100000000

The vacuum_freeze_min_age is the default at 100 million (I assume).

How much is the age decremented by on a vacuum run then?