Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.89) (envelope-from ) id 1h6H5C-0000n6-AT for pgsql-hackers@arkaria.postgresql.org; Tue, 19 Mar 2019 15:55:18 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.89) (envelope-from ) id 1h6H5B-0001Rx-2D for pgsql-hackers@arkaria.postgresql.org; Tue, 19 Mar 2019 15:55:17 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.89) (envelope-from ) id 1h6H5A-0001Rp-Qi for pgsql-hackers@lists.postgresql.org; Tue, 19 Mar 2019 15:55:16 +0000 Received: from gauss.credativ.com ([93.94.130.89]) by magus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.89) (envelope-from ) id 1h6H58-0000Vr-DM for pgsql-hackers@lists.postgresql.org; Tue, 19 Mar 2019 15:55:16 +0000 Received: from gauss.credativ.com (localhost [127.0.0.1]) by gauss.credativ.com (Postfix) with ESMTP id 839AA1E48F2; Tue, 19 Mar 2019 16:55:13 +0100 (CET) Received: from kohn (ipb218f92c.dynamic.kabel-deutschland.de [178.24.249.44]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: mba@gauss.credativ.com) by gauss.credativ.com (Postfix) with ESMTPSA id 06BAB1E1834; Tue, 19 Mar 2019 16:55:12 +0100 (CET) Message-ID: <1553010912.9697.53.camel@credativ.de> Subject: Re: Offline enabling/disabling of data checksums From: Michael Banck To: Andres Freund , Michael Paquier Cc: Magnus Hagander , Fabien COELHO , Sergei Kornilov , PostgreSQL Developers Date: Tue, 19 Mar 2019 16:55:12 +0100 In-Reply-To: <20190319153626.vgxcem5r65yhydck@alap3.anarazel.de> References: <1552475364.4947.64.camel@credativ.de> <20190313115633.GA1878@paquier.xyz> <20190314043936.GH3493@paquier.xyz> <1552577180.9697.4.camel@credativ.de> <20190315025027.GN3493@paquier.xyz> <1552650841.9697.22.camel@credativ.de> <20190315122309.GA1434@paquier.xyz> <1552653447.9697.24.camel@credativ.de> <20190318081301.GH1885@paquier.xyz> <20190319153626.vgxcem5r65yhydck@alap3.anarazel.de> Organization: credativ GmbH Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.22.6-1+deb9u1 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Precedence: bulk Hi, Am Dienstag, den 19.03.2019, 08:36 -0700 schrieb Andres Freund: > On 2019-03-18 17:13:01 +0900, Michael Paquier wrote: > > +/* > > + * Locations of persistent and temporary control files. The control > > + * file gets renamed into a temporary location when enabling checksums > > + * to prevent a parallel startup of Postgres. > > + */ > > +#define CONTROL_FILE_PATH "global/pg_control" > > +#define CONTROL_FILE_PATH_TEMP CONTROL_FILE_PATH ".pg_checksums_in_progress" > > I think this should be outright rejected. Again, you're making the > control file into something it isn't. And there's no buyin for this as > far as I can tell outside of Fabien and you. For crying out loud, if the > server crashes during this YOU'VE CORRUPTED THE CLUSTER. The cluster is supposed to be offline during this. This is just an additional precaution so that nobody starts it during the operation - similar to how pg_upgrade disables the old data directory. Michael -- Michael Banck Projektleiter / Senior Berater Tel.: +49 2166 9901-171 Fax: +49 2166 9901-100 Email: michael.banck@credativ.de credativ GmbH, HRB Mönchengladbach 12080 USt-ID-Nummer: DE204566209 Trompeterallee 108, 41189 Mönchengladbach Geschäftsführung: Dr. Michael Meskes, Jörg Folz, Sascha Heuer Unser Umgang mit personenbezogenen Daten unterliegt folgenden Bestimmungen: https://www.credativ.de/datenschutz