Re: Configure autovacuum

On Fri, Jun 14, 2024 at 2:20 AM Shenavai, Manuel <manuel(dot)shenavai(at)sap(dot)com>
wrote:

> Hi everyone,
>
>
>
> I would like to configure the autovacuum in a way that it runs very
> frequently (i.e. after each update-statement). I tried the following
> settings on my table:
>
> alter table mytable set (autovacuum_vacuum_scale_factor = 0.0);
>
> alter table mytable set (autovacuum_vacuum_cost_delay = 0.0);
>
> alter table mytable set (autovacuum_vacuum_cost_limit = 10000);
>
> alter table mytable set (autovacuum_vacuum_threshold = 1);
>
>
>
> I do a lot of updates on a single tuple and I would expect that the
> autovacuum would start basically after each update (due to
> autovacuum_vacuum_threshold=1). But the autovacuum is not running.
>

HOT is probably what you're looking for:
https://www.postgresql.org/docs/14/storage-hot.html

Presuming that the field you're updating is not indexed, and the table can
be exclusively locked for as long as it takes to rewrite it: give the table
"more space to work" in each page:
ALTER TABLE foo SET (fillfactor = 30);
VACUUM FULL foo;

Then you don't need to VACUUM soooo frequently.