Re: Why doesn't autovacuum/analyze run in due time after calling pg_stat_reset?

On 8/20/23 20:22, Adrian Klaver wrote:
> On 8/18/23 22:35, Rihad wrote:
>> On 8/17/23 13:01, rihad wrote:
>>>
>>> Hi, all. After calling pg_stat_reset all statistics used by
>>> autovacuum got zeroed, and started accumulating from scratch. Some
>>> tables get acted upon properly, some don't.
>>>
>>>
>> Self-replying: yup, it seems there's an arbitrary limit of 100K of
>> n_live_tup after which autovac/analyze kicks in, or it seems so.
>
> To know rather then guess read:
>
> https://www.postgresql.org/docs/current/routine-vacuuming.html#AUTOVACUUM

Sure, I read it before asking.

Taking the first table in the list as an example:

        relname          | n_live_tup | n_dead_tup |   left   |
n_mod_since_analyze |  left
--------------------------+------------+------------+----------+---------------------+--------
fooooooooooo             |      32781 |     240663 |  -234057 |
             513265 | -509937

n_dead_tup (not the actual value, but some time after calling
pg_stat_reset) is much larger than 20% of n_live_tup 32781, and
n_mod_since_analyze is much larger than 10% of it.

Yet it is kept unvacuumed and unanalyzed for a long time.

autovacuum_(vacuum|analyze)_threshold is 50.

What am I missing?

>
>>
>> There are still many tables waiting for their turn, which is long due.
>>
>> Although there are some tables having only 60-70 (not 60-70K)
>> n_live_tup that have had autovacuum run on them. Weird.
>>
>>
>>
>
>