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 4.92) (envelope-from ) id 1jFPXi-0002MG-5v for pgsql-admin@arkaria.postgresql.org; Fri, 20 Mar 2020 21:51:02 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.89) (envelope-from ) id 1jFPXe-0003n4-Nc for pgsql-admin@arkaria.postgresql.org; Fri, 20 Mar 2020 21:50:58 +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 1jFPXe-0003mx-E3 for pgsql-admin@lists.postgresql.org; Fri, 20 Mar 2020 21:50:58 +0000 Received: from excelsior.roeckx.be ([2a05:7300:0:100::3]) by magus.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1jFPXc-0007BP-Ch for pgsql-admin@lists.postgresql.org; Fri, 20 Mar 2020 21:50:58 +0000 Received: from intrepid.roeckx.be (localhost [127.0.0.1]) by excelsior.roeckx.be (Postfix) with ESMTP id 83384A8A1423 for ; Fri, 20 Mar 2020 21:50:54 +0000 (UTC) Received: by intrepid.roeckx.be (Postfix, from userid 1000) id 4D3751FE0CC9; Fri, 20 Mar 2020 22:50:54 +0100 (CET) Date: Fri, 20 Mar 2020 22:50:53 +0100 From: Kurt Roeckx To: pgsql-admin@lists.postgresql.org Subject: Append only tables Message-ID: <20200320215053.GH22330@roeckx.be> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Precedence: bulk Hi, I have a few tables that are append only. Thre are only gets insert and select queries, never update or delete. What I see is that every file is still being updated. It's currently about 500 GB big, and every of that almost 500 files has been touched the past 24 hours. I assume that that the free space map is being used, and that it still finds places where it can insert a row in one of the files. (auto) vacuum is not happening on the table. Is there a way I can turn off this behaviour, and that it really only writes to the last few pages? Kurt