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 1hgDGr-0001Ll-4L for pgsql-performance@arkaria.postgresql.org; Wed, 26 Jun 2019 19:07:53 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.89) (envelope-from ) id 1hgDGp-0003ZS-UL for pgsql-performance@arkaria.postgresql.org; Wed, 26 Jun 2019 19:07:51 +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 1hgDGp-0003ZL-Lx for pgsql-performance@lists.postgresql.org; Wed, 26 Jun 2019 19:07:51 +0000 Received: from mail-qt1-x844.google.com ([2607:f8b0:4864:20::844]) by magus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.89) (envelope-from ) id 1hgDGm-0002Uz-PW for pgsql-performance@lists.postgresql.org; Wed, 26 Jun 2019 19:07:51 +0000 Received: by mail-qt1-x844.google.com with SMTP id x47so3582117qtk.11 for ; Wed, 26 Jun 2019 12:07:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=2ndquadrant-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:mime-version:content-disposition :content-transfer-encoding:in-reply-to:user-agent; bh=Ptj4ijbVuzAmg9bcTQkgou/u3Uz8ew96NZhoykVaX3Y=; b=cd2bO+du2ceu4hycTy7brKRrkYgfzK9PHnKhwKw35y1a26NfRJ7DBFbQKPyVmzancS 86T8MupAoOoHdoQ1WJaM8AYbq00IirVJeOVEIrebceegCqz6l41hOWOVKR1IAurIXyvV 5DyPqydBdLkvqL8Nc39sQAQYaZQMLRNu4IBYILVdq9QlPntTvbCVpvprwAaCb6KarOA5 5O7AoUj1/EXZj+C4a7rjv8UD9gZjKM+v7aL31NvRg0Oce4mG4UWphnbRbjBH9V5SwIuT T+u9tnqiviXQBZj2of5mHH+wG724f/uviv8z4fMWvcTgfBFEFq+I3NcMboHlxPE+k/K+ gAAg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=Ptj4ijbVuzAmg9bcTQkgou/u3Uz8ew96NZhoykVaX3Y=; b=faDqg4QxkefhMuvlscyhd8FXsGMXaYIy5E6fB9U/unPqivgsPriQTxw8R/LUVeFHzS dWvcMkuG4f21K7OGx7ayFarasr66LMatsGKwkGcWew24I7Wzb0ACl81E1zaWfRGbbXSo QnlT6pwOADfAulC4NnXEJt2dq3MPSVHvya5qjzSqrbmRaznhHiadN4q8t6R05zXqh9iB EsjpDZW2Vp4vvEzE2mwO56czDMpqbhWBB9f/Qq8IZbnEcUkjb0e3nZiBbPyj8LZJoRCb vMN0/vveAl+6MNsZ05H02GFg+Pp9KObRVpL36HrhMWFBvA1YbclZh9SNH6PFnHbGtooe 59sQ== X-Gm-Message-State: APjAAAWVIkzrItDyW4yknIHXODrixd7zNrHETe3rGRCaWcLZGCUxLZn6 AEMKT1P2QGYaeoyDwBp1BniuMYG70vKG4DfziekdkiLrnfrxp2EWbEm7qXAkrUXCRQudzLz3hw7 3SpiDRuWSeLcikwgNzW/bnB8T5XG9npiIeXruH9ThTUOhcmRm6bo1y6SJy0HXrf6vmb9porRlaw 4oJuJm+oi8Wx/2V8HqF88= X-Google-Smtp-Source: APXvYqw1d90JWO20F1+Rt/amARTCX4FmM/CyaLYWoPZT6WIXfZ1sYAXqI5poOq944PwAnLIJ6FvTkA== X-Received: by 2002:a0c:981b:: with SMTP id c27mr5008394qvd.48.1561576066270; Wed, 26 Jun 2019 12:07:46 -0700 (PDT) Received: from nimloth.alvh.no-ip.org ([190.121.29.3]) by smtp.gmail.com with ESMTPSA id f6sm8379501qkk.79.2019.06.26.12.07.45 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Wed, 26 Jun 2019 12:07:45 -0700 (PDT) Received: by nimloth.alvh.no-ip.org (Postfix, from userid 1000) id ABA00120770; Wed, 26 Jun 2019 15:07:43 -0400 (-04) Date: Wed, 26 Jun 2019 15:07:43 -0400 From: Alvaro Herrera To: Hugh Ranalli Cc: Justin Pryzby , pgsql-performance@lists.postgresql.org Subject: Re: Perplexing, regular decline in performance Message-ID: <20190626190743.GA15026@alvherre.pgsql> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Precedence: bulk On 2019-Jun-26, Hugh Ranalli wrote: > From my research in preparing for the upgrade, I understood transparent > huge pages were a good thing, and should be enabled. Is this not correct? It is not. > Wouldn't the plan be the same at both > the start of the week (when the problematic table is essentially empty) and > at the end (when it is much larger)? Not necessarily. Though, if a plan change was the culprit you would probably see a sudden change in performance characteristics rather than gradual. Worth making sure, anyway. -- Álvaro Herrera https://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services