Re: max_fsm_pages - Mailing list pgsql-admin

From Tom Lane
Subject Re: max_fsm_pages
Date
Msg-id 12061.1062717844@sss.pgh.pa.us
Whole thread Raw
In response to max_fsm_pages  ("Jouneau Luc" <Luc.Jouneau@diamant.jouy.inra.fr>)
List pgsql-admin
"Jouneau Luc" <Luc.Jouneau@jouy.inra.fr> writes:
> INFO:  Pages 11944: Changed 11944, Empty 0; Tup 32: Vac 1931936, Keep 0, Un=
> Used 0.
>         Total CPU 1.57s/1.90u sec elapsed 42.01 sec.

> It seems that FSM traced all of my deletes since it mentions removes in 864=
> 1+3303=3D11944 pages (>10000 which was set for max_fsm_page).

The numbers output by VACUUM don't tell you anything about how many of
those pages will actually be remembered in the FSM.

In practice, max_fsm_relations=100 is too small; we've bumped the
default to 1000 for 7.4.

> My first aim was to know if max_fsm_pages was set for each table or for a w=
> hole database.

Whole database.  That default setting is very small, too (enough for
a database of maybe a couple hundred meg, at most).

            regards, tom lane

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