From: "Shinoda, Noriyoshi (PSD Japan FSI)" <noriyoshi.shinoda@hpe.com>
To: Michael Paquier <michael@paquier.xyz>, Naga Appani <nagnrik@gmail.com>
CC: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>,
        Tomas Vondra
	<tomas@vondra.me>, Xuneng Zhou <xunengzhou@gmail.com>,
        torikoshia
	<torikoshia@oss.nttdata.com>,
        Kirill Reshke <reshkekirill@gmail.com>,
        "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: RE: [Proposal] Expose internal MultiXact member count function for
 efficient monitoring
Thread-Topic: [Proposal] Expose internal MultiXact member count function for
 efficient monitoring
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Date: Mon, 13 Apr 2026 01:28:55 +0000
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Hi, thanks to the developers and reviewers.

It seems the data type of "num_mxids", which is the result of the "pg_get_m=
ultixact_stats" function, does not match the documentation.=20
In pg_proc.dat, the data type is int8.
[pg_proc.dat]
+  proname =3D> 'pg_get_multixact_stats', provolatile =3D> 'v',
+  proallargtypes =3D> '{int8,int8,int8,xid}', proargmodes =3D> '{o,o,o,o}'=
,

However, the documentation specifies it as an "integer".
[func-info.sgml]
+        ( <parameter>num_mxids</parameter> <type>integer</type>,
+          <parameter>num_members</parameter> <type>bigint</type>,

There may be debate about whether uint32 should be called integer or bigint=
, but I think it's better if the implementation and documentation are consi=
stent. The small attached patch changes the data type of the num_mxids colu=
mn in the documentation to "bigint" to match the implementation.

Regards,
Noriyoshi Shinoda

-----Original Message-----
From: Michael Paquier <michael@paquier.xyz>=20
Sent: Tuesday, December 30, 2025 4:44 PM
To: Naga Appani <nagnrik@gmail.com>
Cc: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>; Tomas Vondra <tomas@vond=
ra.me>; Xuneng Zhou <xunengzhou@gmail.com>; torikoshia <torikoshia@oss.nttd=
ata.com>; Kirill Reshke <reshkekirill@gmail.com>; pgsql-hackers@postgresql.=
org
Subject: Re: [Proposal] Expose internal MultiXact member count function for=
 efficient monitoring

On Mon, Dec 29, 2025 at 08:57:11PM -0600, Naga Appani wrote:
> The oldest_multixact correctly advances to reflect the cleanup.
>=20
> Thanks for adding the pg_read_all_stats privilege check!
>=20
> I think this is ready for RFC.

Thanks for looking.  I have done an extra round of brush-up, then applied t=
he set.  The buildfarm looks OK with it.
--
Michael

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