Re: autoanalyze did not run - Mailing list pgsql-admin

On Tue, Jan 27, 2026 at 1:40 PM Олег Самойлов <splarv@ya.ru> wrote:
> ----------------
> Кому: Олег Самойлов (splarv@ya.ru), Pgsql-admin (pgsql-admin@lists.postgresql.org);
> Тема: autoanalyze did not run;
> 26.01.2026, 19:03, "Laurenz Albe" <laurenz.albe@cybertec.at>:
>
> On Mon, 2026-01-26 at 17:35 +0300, Олег Самойлов wrote:
>
>  > > I try to investigate why autoanalyze did not run in time of our initial
>  > > loading data. Yes, I know, running analyze manually is highly
>  > > recommended in such case. But is must run automatically too.
>  > >
>  > > PostgreSQL 17.7 (Debian 17.7-3.pgdg13+1) on x86_64-pc-linux-gnu,
>  > > compiled by gcc (Debian 14.2.0-19) 14.2.0, 64-bit (from PGDG)
>  >
>  > Are you sure that you committed the transaction?
>
>  I am very sure, thats why there are 13844347 rows in that table. By single copy.
>  >
>  > Is "track_activities" set to "on"?
>
>  I checked, yep.
>
>
> Then the only explanation is that all autovacuum workers are active, and this
> table is starved. See how many autovacuum workers are visible in pg_stat_activity
> and compare that to autovacuum_max_workers.
>
> Yours,
> Laurenz Albe
>
> Now 0. But they worked. The reason is other. Look, first of all, there was not a statistic reset.
> SELECT stats_reset is null FROM pg_stat_database WHERE datname = current_database();
>  ?column?\c
> ----------
>  t
> (1 row)
>  select analyze_count,autoanalyze_count,reltuples, n_live_tup, n_tup_ins, n_tup_upd, n_mod_since_analyze from
pg_stat_user_tablesas s join pg_class as c on (s.relid=c.oid) where relkind='r' and reltuples>0 limit 10; 
>  analyze_count | autoanalyze_count |   reltuples   | n_live_tup | n_tup_ins | n_tup_upd | n_mod_since_analyze
> ---------------+-------------------+---------------+------------+-----------+-----------+---------------------
>              0 |                 0 |             8 |          0 |         0 |         0 |                   0
>              0 |                 0 |         76596 |          0 |         0 |         0 |                   0
>              0 |                 0 |        140997 |          0 |         0 |         0 |                   0
>              0 |                 0 |  2.088436e+07 |          0 |         0 |         0 |                   0
>              0 |                 0 | 1.2661012e+07 |          0 |         0 |         0 |                   0
>              0 |                 0 |  2.288401e+07 |          0 |         0 |         0 |                   0
>              0 |                 0 |         99926 |          0 |         0 |         0 |                   0
>              0 |                 0 | 1.5620866e+07 |          0 |         0 |         0 |                   0
>              0 |                 0 |         17511 |          0 |         0 |         0 |                   0
>              0 |                 0 |        400926 |          0 |         0 |         0 |                   0
> The reason is the n_mod_since_analyze is 0. Thats why autoanalyze didn't started.

Hello,

I do apologize if I mix something up now, but I would expect COPY to
have an effect on "n_ins_since_vacuum" but not "n_mod_since_analyze".
COPY inserts rows, it does not update them.

With best regards,
--
Kristjan Mustkivi

Email: kristjan.mustkivi@gmail.com