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 4.98.2) (envelope-from ) id 1x9Y8A-000000025VR-1MMY for pgsql-bugs@arkaria.postgresql.org; Thu, 24 Sep 2026 01:20:10 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.98.2) (envelope-from ) id 1x9Y89-00000008gj1-2MHp for pgsql-bugs@arkaria.postgresql.org; Thu, 24 Sep 2026 01:20:09 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1x9Y89-00000008gis-1LYZ for pgsql-bugs@lists.postgresql.org; Thu, 24 Sep 2026 01:20:09 +0000 Received: from fout-b6-smtp.messagingengine.com ([202.12.124.149]) by magus.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1x9Y87-00000000yhy-0T37 for pgsql-bugs@lists.postgresql.org; Thu, 24 Sep 2026 01:20:09 +0000 Received: from phl-compute-08.internal (phl-compute-08.internal [10.202.2.48]) by mailfout.stl.internal (Postfix) with ESMTP id 37F731D000CA; Wed, 23 Sep 2026 21:20:04 -0400 (EDT) Received: from phl-frontend-04 ([10.202.2.163]) by phl-compute-08.internal (MEProxy); Wed, 23 Sep 2026 21:20:04 -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=1790212804; x=1790299204; bh=ZN5rv3hU1e yKXjda457TT2sIXNrMJpWlmmVbWyX7+lw=; b=x5PMxkhAqhC65r2g31eaVwHmzG FpK/tF5uLQtMaLpvk30Um2dxQfvUlTFRSh1ZDJmq/bH4imn0vsQp3/j5qKUez0Nw A3+6Se9JAfmt24WvYfSJUHNClF0NLi+1AZphhYOpWVMy1fP6tRvjOANOuY7FEfUl t3yMtt2CkrKwL2hyRSdOO2ipkbXGgrWZ0VN2au1+q7EYWbN2t1oueb4jIFtBFnNv HaFKWVKlaVYgykw0soMgI+qOS44F1UripwZeKILllnnHls7MmgchZWq34HoeAx8P gAlYIqpgyq2UTUOoyxYfYzRcsZX0+UiX6wG1OUopb2xvMN9lrx+5DEvsk5Cw== 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= 1790212804; x=1790299204; bh=ZN5rv3hU1eyKXjda457TT2sIXNrMJpWlmmV bWyX7+lw=; b=cln1NUj8Z2lEcgzhFuoWaKSmpa1+hATEZj3VK+bDFIu+guu749E 8RenAIGbuGVTH0s58F5V3WVCbyQyOzyI+ImGU8tjSX4y+6+ps/yIxxzYx455MGuY Em1KkHi6wjiUSWzfyeoPKn3Bx89TL2KSHkPR0Ku/KSXXyZB/jpKQkf/K9hw/wpj7 hmWHoNVte+s+cRh4HFOHUl+0fUiMhM0CgE9nse299XgZ/ZeIW5dEVliiwoGfI0so xs/sdVvIOQrbn1gJ73HqXYgz60azDxQhtDtpk0lkpK+aQkRrTcRYRoxND7H2SuJP koifaqlPiBdz0fedLExythggFSZ/zJw+W+Q== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: dmFkZTEJStIuJKYtMEpvsod/laLomwAS3SA7hJIbilXXghlr3C+t086c8M63Bx1onx5LL8 cI/Ni91vkzVSVyEr2pliwwhzhusufcJ4OIE1LpiyBx/K8zjUuHpLSJiBIVzf5nRZYZoF/l tpY5RP3d6RIFjcnocX1/DUvNQElloINF9gA9oc6O0nKpW6TaxA89l0f2KtqQ5Elipir/Wp QbCN7YJCIZx2v6lm1z62hbJ7WekBNWkZmdynFjbFOBmNTwgUVELbDvqYP7fPkVreL15pGi G6tMttGPnMP8pAG7ztdoHtAVXFHzLowCAbQ2fI3f5j8P0Njz1P3dMxyIsicJtCcxhUEsid ZoZXpENay1EP9qOej0X89hLo4Qz1/n7tGSrnR2vyV1bDy3wlXMy9FaezzCRpF5Bt0JaGjW lAVwQVgBx7r4fljFA/fTIxPX0XCvdLO/fX+WTYxis1iznaGJGLFHK1vLCKSsc+SJ7229ss oC2iXyv/gkrhgX/Nw4XJVXLbcCHHvfZon1y+1t1Q66SntH/AmpA2sNqOVcipRo2hucvFNU QXpLekokbKBMEA24pQumc+K9wo949UXZ/LHFybUTfrzZOhf5ElivH8aEeVRjPG5LUCJYSb ptcUoE0NvFMkzswBmotPF6uipnFe5WJ1G24YxkefKQ5+DxXcHSpFJTAgmxfQ X-ME-Proxy: Feedback-ID: i0fe9450f:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Wed, 23 Sep 2026 21:20:01 -0400 (EDT) Date: Thu, 24 Sep 2026 10:19:58 +0900 From: Michael Paquier To: Ayush Tiwari Cc: Alexander Lakhin , pgsql-bugs@lists.postgresql.org, Alexandre Felipe , Andres Freund , Peter Eisentraut Subject: Re: BUG #19687: ALTER SEQUENCE provokes error XX001 could not read blocks Message-ID: References: <19687-dd094472b0c48afb@postgresql.org> <7ac90032-cf60-4415-a7f9-cf512196db35@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="Eu1MP3vlYSnvq2nU" Content-Disposition: inline In-Reply-To: List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk --Eu1MP3vlYSnvq2nU Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Thu, Sep 24, 2026 at 01:09:12AM +0530, Ayush Tiwari wrote: > I don't have much background on the lock levels needed here, but taking > AccessExclusiveLock upfront seems reasonable given the storage replacement. > I'm less sure whether it's too strong for cases like OWNED BY. > [I've sent a diff upthread, can add a patch if that's the right way to go] > > Cc'ing Andres, Michael and Peter, who were involved in the original > sequence locking and transactional changes. Does this approach make > sense, or am I missing something here? Where do you mean to add this extra level of locking? -- Michael --Eu1MP3vlYSnvq2nU Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEEG72nH6vTowiyblFKnvQgOdbyQH0FAmq0er4ACgkQnvQgOdby QH3RNRAAio6zaJ+VfgTP89hZOw63wtQnqpGArVN/cT6f75EIHdqVoQuS6iNB9me6 JJGDVs8K6KcP67dWNr92GPFZ6w++1al2bJ3Mxdaz7Jze0NJqMr9b4ao3CwrBYAbl zXC+STAL02BfBlc5lzTdNyeIcHie3jE1sVFv3F2u06p8aKzeHAFfJ7Fok1T2T7uR +3Legy1P19pkXwI0HRNvzZQWSh6zA8FWoC+zX+DlC8YoPSqShD9BNhGGqcbA/iDn mGebED7IQ4Dz4LuLAA/8K2Cq9ram/KbOxhxGCUavjsJAYXHiKmWu9j0ujnT90FV/ 85p56IhFtCaGwYf2LJBr/XHrZdcTPJGhPKtqm1x+5uDCo5oEqxOKVpmpkqJb691b co0R5XXFlfBPe55DmWq4KlP0a3FOyRHliuYqwZgUxJL0kiOIid4YtydjhlzI2iw8 gQTTJduMBfdknx9dtoEIvMwkKyPyYfyLBmAwdMUFsgn9RBdsFaGhgNqdIeHRgb6a 2KBwr95j+2RmbYNS6r1xEV8dpmBH7DckRkFJtrXws/vzIR9E9bPWGvZnhHrtZCU8 RWgFcnEQvzI6eDMKPhyUISgu1cCYNzNDwFgjtlMPJFEr5HwazufB59Jk8hqYGT0c k2LpQOHtUXZpb854n5wFAZHlln3h8Ssw29zhNJbTCHQiY9NIe/4= =hScc -----END PGP SIGNATURE----- --Eu1MP3vlYSnvq2nU--