Обсуждение: Re: pgsql: Consolidate docs for vacuum-related GUCs in new subsection

On 2025-Jan-13, Melanie Plageman wrote:

> Since I didn't hear back about this and I don't see an obvious
> alternative reorganization in guc_tables.c, I plan to just push the
> attached patch that updates only postgresql.conf.sample.

Apologies, I was very unclear -- I didn't want to talk about the
ordering of entries in the code, but the categorization.  See the
config_group_names list in guc_tables.c, which defines some groups.
Each setting belongs into a group, and those groups correspond to what
the sample config file lists as section/subsection titles and to the
grouping in the docs.  Also, this categorization affects how the entries
are listed in the pg_settings view and in "postgres --describe-config",
which feed from the same tables.

Perhaps with your changes (assuming I read your commit message right),
we need new groups:
VACUUMING
VACUUMING_FREEZING
VACUUMING_AUTOVACUUM

Thanks

-- 
Álvaro Herrera        Breisgau, Deutschland  —  https://www.EnterpriseDB.com/
"Doing what he did amounts to sticking his fingers under the hood of the
implementation; if he gets his fingers burnt, it's his problem."  (Tom Lane)

Hi!

On Mon, Jan 13, 2025 at 3:46 PM Alvaro Herrera <alvherre@alvh.no-ip.org> wrote:

On 2025-Jan-13, Melanie Plageman wrote:

Since I didn't hear back about this and I don't see an obvious
alternative reorganization in guc_tables.c, I plan to just push the
attached patch that updates only postgresql.conf.sample.

Apologies, I was very unclear -- I didn't want to talk about the
ordering of entries in the code, but the categorization.  See the
config_group_names list in guc_tables.c, which defines some groups.
Each setting belongs into a group, and those groups correspond to what
the sample config file lists as section/subsection titles and to the
grouping in the docs.  Also, this categorization affects how the entries
are listed in the pg_settings view and in "postgres --describe-config",
which feed from the same tables.

Oh dear, I had no idea that these categories existed. I suppose I
never paid attention to the category column in pg_settings nor used
--describe-config. Attached is a patch to fix this. I checked both
pg_settings and --describe-config output, and it seems to work.

I'm quite sorry about the extra noise this is causing (especially for
people with patch sets requiring rebasing).

Perhaps with your changes (assuming I read your commit message right),
we need new groups:
VACUUMING
VACUUMING_FREEZING
VACUUMING_AUTOVACUUM

I've gone with VACUUM_AUTOVACUUM, VACUUM_COST_DELAY, and
VACUUM_FREEZING, but I am open to feedback.

Looks good and convenient, thanks for the patch!

I noticed another guc autovacuum_work_mem, which belongs more to the autovacuum category in my opinion, although it belongs to RESOURCES_MEM, but in fact, only autovacuum uses it.

-- 
Regards,
Alena Rybakina
Postgres Professional