Feedback-ID: i1ff147bf:Fastmail
From: =?utf-8?Q?Dagfinn_Ilmari_Manns=C3=A5ker?= <ilmari@ilmari.org>
To: Melanie Plageman <melanieplageman@gmail.com>
Cc: Kirill Reshke <reshkekirill@gmail.com>,  Andres Freund
 <andres@anarazel.de>,  Robert Haas <robertmhaas@gmail.com>,  Andrey
 Borodin <x4mmm@yandex-team.ru>,  PostgreSQL Hackers
 <pgsql-hackers@lists.postgresql.org>,  Heikki Linnakangas
 <hlinnaka@iki.fi>
Subject: Re: eliminate xl_heap_visible to reduce WAL (and eventually set VM
 on-access)
References: 
 <CAAKRu_YX0NP_yhXvPnvDRjVxxprsRBM-_MZzAJskfMydMQ=ETA@mail.gmail.com>
	<CA+TgmoZef8XqRujP1NN=wJdV4SxOtu7rxRozsyAtaEvuVMZhEw@mail.gmail.com>
	<CAAKRu_YxD3UC3BXxS55jPjBC_yj_vn3FVoLvBMwQuHXGDXacGg@mail.gmail.com>
	<CA+TgmobYY2URHKBMh1NHo1zF3Z28TiS_+0aSyRYyBfvauCPZzA@mail.gmail.com>
	<CAAKRu_YOJ3VTKo4Z9vB2hGeTnwVWsL39gXH09vyBUQ7bGtDnKA@mail.gmail.com>
	<yn4zp35kkdsjx6wf47zcfmxgexxt4h2og47pvnw2x5ifyrs3qc@7uw6jyyxuyf7>
	<CAAKRu_ZiuR+YcUc7=TrgANbRakpzCu8X9zqR=Tf0fE6uDbfP1g@mail.gmail.com>
	<CA+TgmoYgCs=SEsohP6Z6R3KKsGaqFqvqxH8vQ_-nY4t+7rK8jg@mail.gmail.com>
	<CAAKRu_ZP-3=SaZykpwDBMJOdUKyW3Wm5JZfPFRR3L5Ac8ouq4w@mail.gmail.com>
	<CAAKRu_bgkOQqu3K5n4YLRsNBZqJ9Rjg80ROqgKSr2UGz4b5hUg@mail.gmail.com>
	<2wk7jo4m4qwh5sn33pfgerdjfujebbccsmmlownybddbh6nawl@mdyyqpqzxjek>
	<CAAKRu_YR-COJ9aGnMUQqt5yoWmUBjikqrd4jGNZYouHaXpis9g@mail.gmail.com>
	<CALdSSPhiCwJwWwgJP1NmqRmnp9RS2tGOBY0gQrfLCbB+OS5_KQ@mail.gmail.com>
	<CAAKRu_YS+Ocm=OzMaZnG4egFiE9v4VYfZ25DXd6jbwegqmGYbQ@mail.gmail.com>
	<CAAKRu_ZGZSqhGt-RcmmfiSheC+1fjQdxy6_+oM-1jMn8hyVptQ@mail.gmail.com>
	<CALdSSPg+B8RTzTXhJvCcKJBqgzhPZkq0E2oqxQdv74ZNZOMVzg@mail.gmail.com>
	<CAAKRu_Zha7HcdQBv8tTtQrcry5332J6kHnOc1X=TT03LzUXDow@mail.gmail.com>
Date: Thu, 20 Nov 2025 17:55:05 +0000
In-Reply-To: 
 <CAAKRu_Zha7HcdQBv8tTtQrcry5332J6kHnOc1X=TT03LzUXDow@mail.gmail.com>
	(Melanie Plageman's message of "Wed, 19 Nov 2025 18:13:30 -0500")
Message-ID: <87see87fnq.fsf@wibble.ilmari.org>
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.2 (gnu/linux)
MIME-Version: 1.0
Content-Type: text/plain
Archived-At: 
 <https://www.postgresql.org/message-id/87see87fnq.fsf%40wibble.ilmari.org>
Precedence: bulk

Melanie Plageman <melanieplageman@gmail.com> writes:

> +			PruneFreezeParams params = {.relation = relation,.buffer = buffer,
> +				.reason = PRUNE_ON_ACCESS,.options = 0,
> +				.vistest = vistest,.cutoffs = NULL
> +			};

I didn't pay much attention to this thread, so I didn't notice this
until it got committed, but I'd like to lodge an objection to this
formatting, especially the lack of spaces before the field names. This
would be much more readable with one struct field per line, i.e.

	PruneFreezeParams params = {
		.relation = rel,
                .buffer = buf,
		.reason = PRUNE_VACUUM_SCAN,
		.options = HEAP_PAGE_PRUNE_FREEZE,
		.vistest = vacrel->vistest,
		.cutoffs = &vacrel->cutoffs,
	};

or at a pinch, if we're really being stingy with the vertical space:

	PruneFreezeParams params = {
		.relation = rel, .buffer = buf,
                .reason = PRUNE_VACUUM_SCAN, .options = HEAP_PAGE_PRUNE_FREEZE,
		.vistest = vacrel->vistest, .cutoffs = &vacrel->cutoffs,
	};

I had a quick grep, and every other designated struct initialiser I
could find uses the one-field-per-line form, but they're not consistent
about the comma after the last field.  I personally prefer having it, so
that one can add more fields later without having to modify the
unrelated line.

- ilmari