Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1wWSna-002dG6-1T for pgsql-hackers@arkaria.postgresql.org; Mon, 08 Jun 2026 05:45:22 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.96) (envelope-from ) id 1wWSnZ-000o7i-0h for pgsql-hackers@arkaria.postgresql.org; Mon, 08 Jun 2026 05:45:21 +0000 Received: from makus.postgresql.org ([2001:4800:3e1:1::229]) by malur.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1wWSnY-000o7a-1E for pgsql-hackers@lists.postgresql.org; Mon, 08 Jun 2026 05:45:20 +0000 Received: from fhigh-a5-smtp.messagingengine.com ([103.168.172.156]) by makus.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1wWSnV-00000001djW-3Wwi for pgsql-hackers@lists.postgresql.org; Mon, 08 Jun 2026 05:45:19 +0000 Received: from phl-compute-04.internal (phl-compute-04.internal [10.202.2.44]) by mailfhigh.phl.internal (Postfix) with ESMTP id 958B314000D4; Mon, 8 Jun 2026 01:45:16 -0400 (EDT) Received: from phl-frontend-03 ([10.202.2.162]) by phl-compute-04.internal (MEProxy); Mon, 08 Jun 2026 01:45:16 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=paquier.xyz; h= cc:cc:content-type:content-type:date:date:from:from:in-reply-to :in-reply-to:message-id:mime-version:references:reply-to:subject :subject:to:to; s=fm1; t=1780897516; x=1780983916; bh=Gz2gzSFYGk OVH91u1gZIdIRKg9sO1f3feWZKqwtpcto=; b=rDWSVb59k3zNo0SWqBtJjD9iJ2 BxyhLBh2jtdmTfOU9VzNc5hW3wZ0qhMWOplNYO8xGmU21OGzxYDjO8b9fiVEpCY5 dFfj7b3F4dN5kOxv5Hhyn5BebfouI2a/wjsP6M7pL7IX5IJLa02t96Pm+RJ397+x mmcyw2MYGgKDtnqEKAN1sc0fsJE1g8xlCa6BswIcIToJXyEsuXoPcpr7Moc5yOin c8zNVHC4fwQsdllCkEwggOXnwvl0k85Nl3LGkmKiZcyStj7zIpHwMd3Cv7kSqiCn wHTg1/roi/r0w8s4tSRy8RWGEUj3Hh22QAjCpVZFshk9dmjmupLjRwL3+qUQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:content-type:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:subject:subject:to :to:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm1; t= 1780897516; x=1780983916; bh=Gz2gzSFYGkOVH91u1gZIdIRKg9sO1f3feWZ Kqwtpcto=; b=TCmqisGcCsaHOKRZjEt4AYtXL5GW68px/lRJmJFLaswFjuKXzmq ClHYNVBNfSY81lRcvX9RlDdqQ7P6bjcqzrjOqoXhGWrSFD+D2uQeREiq5JWiOeod OQBsq8czIH9RjLM15CCPFYll/58/z7PVZVTXQ6lMW0rg6fInmYT60WGVBhUT93Ix 55t761qxxj5FwPCJMfhIKqOc92WvSvvuKYd4bGyFPq98Apn3U+eGJ+TMJDqG9OFG XS0qzoBRZU5plKllRnt0ZNYzziF8KvWz/6NiaAjnlFh0IPaAputYhlusYPSf6j22 Orgh0ZxEEV3pLAAZsAN8oer8YUd5IrkYsvA== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: dmFkZTFg+cI9B0SK1i00rCZTcPgSEvWsFaDKuXhgH2PSH9EfAEkYvSMm6d4ZWVnBEpCydo MvyZL9X4MdffcAAmaT0yCwEuDWFYQwDVgeywrRLvIw8Le+qGOutJnEvA+GdH7RHBgt2ajw dbmaYxS/MWphHEiyD5zaYcZNrvNUspgXEJhCQ2cXQxwFdpLtER9eb1RPFwqsh0uPNsWvTZ 4dKO1WOcmniGUupHLx+p8RyVUlr3cKUSmV/Q+emsyqs5BQbI8qqo1Bsm06OWlFlybUGEj0 3BDGMgEJSSr/vkNsqV9zb0Plwy/Un0Q1HNc7d5Je6lCzWP8TfCqe3c+fjW7Qkok5tA54Ye vloS17blyNnD9XzanAq9uQBtckiYM8/5vasMt0cLvKFk6tR8tmGhl7XZsDYT8Maj+DGkCP rC2FDpTgTvLdGql/Ovnnm7cui9JH6WOht1kHABMLRxmx5hyNx8EfqJi3r6pW1KIiL05FED 3K770i5Brx7IyJ132EFQg2Muz3/kayKGSvVBJllC1b+MRyQuh+eac6LE1fz0hOlI22/5LV +VSFCIMwxFyh1kUzvN7/PZ2kmVoFcdV9yys4DTFGq6YJOygXP/42Q1VNx0Px3RTnVIYz/f AZlZLdh1iZ0n3uOUFlA2V+ds2ssjPe05p53rtu1Mvz6x+zl0BXI610fT/P+g X-ME-Proxy: Feedback-ID: i0fe9450f:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Mon, 8 Jun 2026 01:45:14 -0400 (EDT) Date: Mon, 8 Jun 2026 14:45:10 +0900 From: Michael Paquier To: Kyotaro Horiguchi Cc: li.evan.chao@gmail.com, pgsql-hackers@lists.postgresql.org Subject: Re: Adjust pg_stat_get_lock() prorows to match lock types Message-ID: References: <75836FCA-2A8A-4DED-A13F-888595460A2D@gmail.com> <20260608.142000.1993011436447649540.horikyota.ntt@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="6ShGDq7qIbblAvuV" Content-Disposition: inline In-Reply-To: <20260608.142000.1993011436447649540.horikyota.ntt@gmail.com> List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk --6ShGDq7qIbblAvuV Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jun 08, 2026 at 02:20:00PM +0900, Kyotaro Horiguchi wrote: > At Mon, 4 May 2026 10:23:47 +0800, Chao Li wrote= in=20 >> I read the code of pg_stat_lock() and played a bit with it. I happened = =3D >> to notice one thing: the function always returns 12 rows, but the =3D >> planner estimates 10 rows: >=20 > I'm not convinced this needs to be adjusted. Neither am I. An estimate does not have to match the exact reality, especially when it comes to these system functions. Just one example =66rom pg_proc.dat: pg_stat_get_io() has a prorows of 30, returns 95 rows. -- Michael --6ShGDq7qIbblAvuV Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEEG72nH6vTowiyblFKnvQgOdbyQH0FAmomVuYACgkQnvQgOdby QH0SiQ/+Jc4/smqWk+A9rIjEHdPNh++i/4H41S/uOo88zYSCKkMWUqflih4oDVa5 HSIc6y3pt4TANNEekuA72Xx9R56sJ0/npgXK/vgh8nMsrM5//CZxh2/4fR0thQJi oMbAPtGivGlkxuzT17g9/4q9LOIyLvpDsZ32M3EQMCc+el81CEvukpYqfFwsMH2y /GdVFh5ez8SM+L1qCJKUUbrsQRCobXju+EnJT7xTbGEjF4eUWcx2sfWU+I/3kGmB cOnHK/yqZ1HH8lpO9qb342PW6zcy5YJjcoUteBLzeAw5/Vrf5HGB1IlnmP+9QjlV OmTG5ZpYEXQXfitVdWWMyvPfBS3GzKWpzlkscbkdeMFixhXeeFTNlz0HlSTPMugH VuCaA7sfnEO6p8qSP5cxqYZpalUtn4L0v6vYSwzFOjW5U/s9RJHG9xomtmVbpsB6 gs+YXOVX/aG2LVKt3qIa3pKu2qvKaI3k9ichXT6avoqQg4t9zUsbZv/gspoe9Q8S LxJpD/n20ll0O2rTAghSGWNl2jrNDzpQ7z6QlhuV61V1rz3ooQ9kO9KPJqDtppVy CDz8zYk0qEAxFOma4E0mHacz7US9cxmCKCNO2Sf2iwMgG1g+ur7TXfendvwhfYeU puc5N/W01x4QfL/RmldMJsi8+JoIH0FBDNdhR8Y1KmHfkTEr0FA= =WmJG -----END PGP SIGNATURE----- --6ShGDq7qIbblAvuV--