Re: template0 is having high age of datforzenxid

Hi,

On 2019-04-02 15:35:53 -0700, AI Rumman wrote:
> I am running Postgresql 10 where I can see the template0 database is having
> longest datfrozenxid:
> ```db_name age_of_datfrozenxid
> --------------------------------------
> postgres 251365
> template1 234574
> template0 75366462
> db1 253097
> db2 250649
> db3 250649
> db4 14641
> db5 14214```
>
> Initially I had high age for all the databases and I ran "vacuum freeze"
> which brought down the age of other databases. But how can I do the same
> for template0?

75 million isn't that high - autovacuum will automatically look at it
once above autovacuum_max_freeze_age (defaulting to 200 million). If
you really for some reason need to make it have a lower datfrozenxid
(why?), you'd need to update its pg_database entry to allow connections,
connect to it, vacuum it, and change datallowconn back.

Greetings,

Andres Freund