Message-ID: <8da558b6-14fe-4f04-a6bd-98e9961c9ff5@iki.fi>
Date: Tue, 6 Jan 2026 17:28:25 +0200
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Subject: Re: [PATCH] Refactor SLRU to always use long file names
To: Aleksander Alekseev <aleksander@tigerdata.com>,
 pgsql-hackers@lists.postgresql.org
Cc: Rustam ALLAKOV <rustamallakov@gmail.com>,
 Michael Paquier <michael@paquier.xyz>
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From: Heikki Linnakangas <hlinnaka@iki.fi>
In-Reply-To: <CAJ7c6TNqaK3R52KiSaR78p7OkC=kccO4FHZaff7F9ijz36ihsw@mail.gmail.com>
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On 06/01/2026 17:18, Aleksander Alekseev wrote:
> +static void
> +check_slru_segment_filenames(void)
> +{
> +	int i;
> +	static const char* dirs[] = {
> +		"pg_xact",
> +		"pg_commit_ts",
> +		"pg_multixact/offsets",
> +		"pg_multixact/members",
> +		"pg_subtrans",
> +		"pg_serial",
> +	};
> +
> +	if(old_cluster.controldata.cat_ver >= SLRU_SEG_FILENAMES_CHANGE_CAT_VER)
> +		return;
> +
> +	for (i = 0; i < sizeof(dirs)/sizeof(dirs[0]); i++)
> +		rename_slru_segments(dirs[i]);
> +}

Since commit bd8d9c9bdf "Widen MultiXactOffset to 64 bits", 
"pg_multixact/members" should not be in that list anymore.

Also, it seems misleading that a function called "check_*" doesn't 
merely check for things, but renames files. Also, it seems silly to 
first copy/link the files with the old short names, and rename them 
later. Could we copy/link them with the new long names to begin with?

(No comment on whether this is a good idea in general or the rest of the 
patch)

- Heikki