From: "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>
To: 'Michael Paquier' <michael@paquier.xyz>
CC: "Aya Iwata (Fujitsu)" <iwata.aya@fujitsu.com>, pgsql-hackers
	<pgsql-hackers@postgresql.org>
Subject: RE: [PROPOSAL] Termination of Background Workers for ALTER/DROP
 DATABASE
Thread-Topic: [PROPOSAL] Termination of Background Workers for ALTER/DROP
 DATABASE
Thread-Index: Adw0Q6iYueu3o2DFQ0mAqFGMYYi8fgCHrYogAANaoAAADGiE4A==
Date: Mon, 6 Oct 2025 09:15:53 +0000
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Precedence: bulk

Dear Michael,

> The main take that I am getting here from Iwata-san is that this would
> lead to less code duplication.  Another item, which you are not
> mentioning, is that this would be more flexible with bgworkers that
> have been starting dynamically, where shared_preload_libraries may not
> be used, still a bgworker would need to react.  So the suggestion of a
> new API to control if a bgworker should be stopped like any other
> backend when there is a database activity worth it is a good one, as
> long as it is in line with what we do with normal backends.

Okay, so this proposal has the advantage that we can terminate workers, eve=
n if the
extensions do not control workers on the shared memory, right?

> AcceptBackgroundWorkerCancel() is going backwards, IMO.  Wouldn't it
> be better to pass it down as an option in bgw_flags, to mark that a
> bgworker connected to a database can be shutdown due to the effect of
> a database getting dropped or moved?

+1 to extend the bgw_flags.

Best regards,
Hayato Kuroda
FUJITSU LIMITED