Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.84_2) (envelope-from ) id 1eBu8j-0005Ns-0u for pgsql-performance@arkaria.postgresql.org; Tue, 07 Nov 2017 03:01:25 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.84_2) (envelope-from ) id 1eBu8i-0005x8-K0 for pgsql-performance@arkaria.postgresql.org; Tue, 07 Nov 2017 03:01:24 +0000 Received: from makus.postgresql.org ([2001:4800:1501:1::229]) by malur.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1eBu6w-00014r-P0 for pgsql-performance@postgresql.org; Tue, 07 Nov 2017 02:59:34 +0000 Received: from mail-oi0-x229.google.com ([2607:f8b0:4003:c06::229]) by makus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.84_2) (envelope-from ) id 1eBu6u-00071M-DI for pgsql-performance@postgresql.org; Tue, 07 Nov 2017 02:59:33 +0000 Received: by mail-oi0-x229.google.com with SMTP id v9so9133155oif.13 for ; Mon, 06 Nov 2017 18:59:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=9oFOCRu/WOB+ted+ta8u+zK0GhXbGDFbhRG9aP+LEPk=; b=lamiL2GFFVP4znCdVCubSrPGYtKofa9Aaot+TeyDlS/f01CaeLwEXxhZ3gM6Df8Wyd gT3LRcWtA4wWX1elTaWP0WUfNlGxkR63P5kaVats57AuVSxOEIyy5Mvx3C5kaob0KihI Y/5EHPrn7wmog/1y3BC/O1O7D5Ti+desOzmPUoJDrdXbtCYfh0jn1S7+E0XhMMOrBqub 3OmLN1HihbOf8Z2qtjjr6B4VW64YyVkDvKmbIjPIQFIupqDOIKAEB8BmtsvoL8uEtM/T AaaUwu+qbzGU7Qr6RCXNlaVRtVjqYZsFJ3pLNn3HFr9/Ryk5L6DSlDkcQ0/6Qdxhy2Wt N/KQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=9oFOCRu/WOB+ted+ta8u+zK0GhXbGDFbhRG9aP+LEPk=; b=C1lqsM/A3s2WrgjRRoBTvj0NXWf5S8+ZaaLKZnrjcCIHiq5vAVYuhuemOr4Czgshvt lGt3+rXiSpJzEk4GyLVibcBAjyWm7EQHdhfbMzMjghqM+mP5WcjPJ9E/G12DVK+U+YHb d9/epSOFrLofysNFsf0YQv9yjMICRghS4tTzMDwjWJtLgjJrdNyL+nqsQYQ4URZqUhXf 9xSA16/A/BiD44eDFP1ae4BVzm3uwsjuFLtvO3Mhg/OLh3LqE4stPyU38VtLZWS45oNv oSbzpsb73Fnkr2U4Nnc1jrLwtO2hqNeXP4DuoJRkp1NoEnDEFOg6kkCJ5MyP1hcNe93j UqRA== X-Gm-Message-State: AMCzsaXgOQBsBKCIz3yDMVlW627v+CmK5uFSoPd+G1tIQoQoXn09vLiZ YM1e2fKMB39tioleJaR2K3tiCw0RWej6Qs1nvKs= X-Google-Smtp-Source: ABhQp+ToR1zuStvWctGb/Es7+qHY1V+GgPCSVPWegXHKlNU7rAtQBvChN7taD3WkJ6heo0PNx+DbKxNX375vldPCk8Q= X-Received: by 10.202.244.78 with SMTP id s75mr9688002oih.24.1510023571423; Mon, 06 Nov 2017 18:59:31 -0800 (PST) MIME-Version: 1.0 Received: by 10.157.6.162 with HTTP; Mon, 6 Nov 2017 18:59:30 -0800 (PST) In-Reply-To: <23D1DA58-FE4A-40BB-83CA-AFEE687D99A6@amplify-nation.com> References: <68F12CAE-BFD8-4E21-8B39-AECB0C5E5A8F@contoso.com> <20171106142142.GD14205@telsasoft.com> <23D1DA58-FE4A-40BB-83CA-AFEE687D99A6@amplify-nation.com> From: Adam Brusselback Date: Mon, 6 Nov 2017 21:59:30 -0500 Message-ID: Subject: Re: Performance loss upgrading from 9.3 to 9.6 To: Adam Torres Cc: Justin Pryzby , "pgsql-performance@postgresql.org" Content-Type: text/plain; charset="UTF-8" List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-performance Precedence: bulk Sender: pgsql-performance-owner@postgresql.org > It has now been decided to try upgrading to 9.4 as that is the minimum to support Django 1.11 (which we are trying to upgrade a backend service to). The hope is whatever feature we have not configured properly in 9.6 is not there in 9.4. It's entirely possible whatever is causing your performance issue is caused by the migration, rather than anything inherently different in 9.6. The best test for that is setting another 9.3 server up, restoring a backup, and testing there. If that is very different than what you are getting on 9.6 then it's something which changed in Postgres, if not it's just bad stats. I do think that it's probably better to fix your query rather than choosing to upgrade to 9.4 rather than 9.6. You have a crazy amount of your query time spent in a single node. That plan is not good. If that's the only query giving you trouble, work on optimizing it. Just my $0.02 -Adam -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance