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 1nDEeO-0004Aw-9h for pgsql-hackers@arkaria.postgresql.org; Thu, 27 Jan 2022 23:58:00 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.92) (envelope-from ) id 1nDEeM-0001Uv-17 for pgsql-hackers@arkaria.postgresql.org; Thu, 27 Jan 2022 23:57:58 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1nDEeL-0001Um-Mj for pgsql-hackers@lists.postgresql.org; Thu, 27 Jan 2022 23:57:57 +0000 Received: from mail-pj1-x102d.google.com ([2607:f8b0:4864:20::102d]) by magus.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1nDEeJ-0005J0-09 for pgsql-hackers@lists.postgresql.org; Thu, 27 Jan 2022 23:57:57 +0000 Received: by mail-pj1-x102d.google.com with SMTP id r59so4861493pjg.4 for ; Thu, 27 Jan 2022 15:57:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=gUvtd+yfOuqfj1wXP757omohlHEXWsZugrYyArLFVpE=; b=UGF/gbNmvGDErovDzLMc+uhwm0Vm6v3xIW0DbDnDkcKELAIpshpqrkV5AYOFqtiy61 q0F8D9Dl4lSAOjuZEO6Cr675nKRUiOK0qMMDzGBvCI8PD41bvBCcdtXCQX3peBzl1nbf hUqgPfXbJxfX9AP6ouOim0j3WM6tajotu9st62V+YmabVLBliBRoqu2VdNIMEE0RClgA ga8AWGBJIuvD74APbJykKxkFaoGtfpjzwYaYehi5cMbrqAXK++Qn1/xl+2kGl/JmLDL4 SHZFVqtVL1R9e+wOWSry63ouOi66tY9XlVROuTxTOjK1BU71wZ1Aa7A11PSfXKPfFL+U iz8A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=gUvtd+yfOuqfj1wXP757omohlHEXWsZugrYyArLFVpE=; b=XHCYp/WsPdyH1XRWAW+L/8CE8bdNODsK4XtenNADnfKfBbY5TR+tEIayJT/qzAmAgN L4JS2Nzd+lKE7dYdF5l7bqnQkoDqYirLgEVfmkKX7MTguGC4R5Gj5ajvaKGwTvOg9nDv WPkY7JeBv8B+EP5hJr268DSQi88/kHs19/5otmL8EfAGRekJb4yZmovCSt9+LpI/jaB7 /nc7x3r4o5SfsqohiXRfKer7FPqIKlRuehxw3hTwG7uvb3l027iw/YNFnqXpgJVu7/AE Q3H21jhO4tl2YVG3vHvVQlSxbkaOUWL6lgYQJrNIs293MZ1ihGP8ozZMIcThgxvcLSIw ntgA== X-Gm-Message-State: AOAM531SOZ9TO6OqmTzz+cJM67jD1NS1w8bGMHF7ezHY7d8iWfzG0a+M tKrH9wxPpU3QdoANzBGpUUo= X-Google-Smtp-Source: ABdhPJwuv/0yEiG45RUlQp43gCbKz3kECsBlMgePwyauoB2DAG2FdRBMlY5imvpzXpJkyuuCVryWSg== X-Received: by 2002:a17:90a:1784:: with SMTP id q4mr16765582pja.3.1643327872777; Thu, 27 Jan 2022 15:57:52 -0800 (PST) Received: from nathanxps13 ([50.54.155.70]) by smtp.gmail.com with ESMTPSA id 19sm390594pja.36.2022.01.27.15.57.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 27 Jan 2022 15:57:52 -0800 (PST) Date: Thu, 27 Jan 2022 15:57:49 -0800 From: Nathan Bossart To: Bharath Rupireddy Cc: "Bossart, Nathan" , Julien Rouhaud , Michael Paquier , Kyotaro Horiguchi , PostgreSQL Hackers Subject: Re: Add checkpoint and redo LSN to LogCheckpointEnd log message Message-ID: <20220127235749.GA558032@nathanxps13> References: <20211224.145134.1164706994861031206.horikyota.ntt@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk On Thu, Jan 27, 2022 at 08:37:37PM +0530, Bharath Rupireddy wrote: > I'm still not clear how the REDO location can be treated as a start > LSN? Can someone throw some light one what this checkpoint's REDO > location is? It's the WAL insert location at the time the checkpoint began (i.e., where you need to begin replaying WAL from after a crash). -- Nathan Bossart Amazon Web Services: https://aws.amazon.com/