Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oprgd-0002d5-72 for pgsql-admin@arkaria.postgresql.org; Tue, 01 Nov 2022 13:52:15 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.92) (envelope-from ) id 1oprgc-00067Z-3O for pgsql-admin@arkaria.postgresql.org; Tue, 01 Nov 2022 13:52:14 +0000 Received: from makus.postgresql.org ([2001:4800:3e1:1::229]) by malur.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oprgb-00067Q-Nj for pgsql-admin@lists.postgresql.org; Tue, 01 Nov 2022 13:52:13 +0000 Received: from mailout.easymail.ca ([64.68.200.34]) by makus.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oprgZ-0007B6-Db for pgsql-admin@lists.postgresql.org; Tue, 01 Nov 2022 13:52:12 +0000 Received: from localhost (localhost [127.0.0.1]) by mailout.easymail.ca (Postfix) with ESMTP id 14714E68D1; Tue, 1 Nov 2022 13:52:09 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at emo08-pco.easydns.vpn Received: from mailout.easymail.ca ([127.0.0.1]) by localhost (emo08-pco.easydns.vpn [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id cC48AoyXxMjS; Tue, 1 Nov 2022 13:52:08 +0000 (UTC) Received: from smtpclient.apple (unknown [165.140.184.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mailout.easymail.ca (Postfix) with ESMTPSA id AC8C8E68B3; Tue, 1 Nov 2022 13:52:08 +0000 (UTC) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3731.200.110.1.12\)) Subject: Re: [External] WAL Replication query From: Scott Ribe In-Reply-To: Date: Tue, 1 Nov 2022 07:51:57 -0600 Cc: Ron , pgsql-admin@lists.postgresql.org Content-Transfer-Encoding: quoted-printable Message-Id: <66DBCDC1-335A-463C-A7B6-8FC79D8548D4@elevated-dev.com> References: <88faef33e966796226022d6e7f3e32ad6c59fcfd.camel@cybertec.at> <8f9e6c92-4daa-a543-6825-05a3503f4296@gmail.com> To: Laurenz Albe X-Mailer: Apple Mail (2.3731.200.110.1.12) List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk > On Nov 1, 2022, at 7:34 AM, Laurenz Albe = wrote: >=20 > Right. And how does that constitute data loss? If you start the = primary again, the transaction > will be replicated just fine. Now if you call it *data delay*, I = would agree. It comes down to this: there is no magic. Replication is async with = delay between primary & secondary, or replication is synchronous with = the delay visible to clients. Transaction commit completes, or it = doesn't. And so on.=