Received: from malur.postgresql.org ([2a02:16a8:dc51::56]) by arkaria.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.89) (envelope-from ) id 1fbMEC-0006Su-Dh for pgsql-docs@arkaria.postgresql.org; Fri, 06 Jul 2018 08:36:33 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.89) (envelope-from ) id 1fbMEB-0004hp-5f for pgsql-docs@arkaria.postgresql.org; Fri, 06 Jul 2018 08:36:31 +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 4.89) (envelope-from ) id 1fbMDg-0002mL-Dh for pgsql-docs@lists.postgresql.org; Fri, 06 Jul 2018 08:36:00 +0000 Received: from mail.postgrespro.ru ([93.174.131.138]) by makus.postgresql.org with esmtp (Exim 4.89) (envelope-from ) id 1fbMDb-0005no-Kn for pgsql-docs@postgresql.org; Fri, 06 Jul 2018 08:35:58 +0000 Received: from localhost (localhost [127.0.0.1]) by mail.postgrespro.ru (Postfix) with ESMTP id EE40421C2AEB for ; Fri, 6 Jul 2018 11:35:52 +0300 (MSK) X-Virus-Scanned: Debian amavisd-new at postgrespro.ru X-Spam-Flag: NO X-Spam-Score: 0 X-Spam-Level: X-Spam-Status: No, score=x tagged_above=-99 required=4 WHITELISTED tests=[] autolearn=unavailable Received: from ars-thinkpad (nat03-43-2.netorn.net [188.35.130.88]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mail.postgrespro.ru (Postfix) with ESMTPSA id C611C21C2A35 for ; Fri, 6 Jul 2018 11:35:52 +0300 (MSK) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=postgrespro.ru; s=mail; t=1530866152; bh=x2kigVJR89BuWNVbY0wzXgZyGiVXfYmJLTA0qdOMPZQ=; h=From:To:Subject:Date; b=He5vNgbIDxIP4ppKRXAMGwmMWIC6m6D6GYOj66swfb7Yx4lLc+9BG3hglYD7xaD3p PFIpQfey8eCMfM5LB8GmdH3A4UCDIsGUEqWDKXhv3U7xZlEU/Qclv6m76E4H+1wa6V TtE6c5rw/HFePn/G+PC5nL2ud3feRLVIY6rRbsWY= User-agent: mu4e 1.1.0; emacs 26.0.50 From: Arseny Sher To: "pgsql-docs\@postgresql.org" Subject: Agressive vacuum meaning Date: Fri, 06 Jul 2018 11:35:52 +0300 Message-ID: <87lgaoiwwn.fsf@ars-thinkpad> MIME-Version: 1.0 Content-Type: text/plain List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Precedence: bulk Hello, I am a bit confused by the following. Apparently what is meant by 'aggressive vacuuming' at [1] and 'aggressive freezing' [2] is not entirely the same: the latter not only visites all the pages, it also freezes all visible tuples (vacuum_freeze_min_age = 0). You might say that *vacuuming* is not *freezing*, so it is fine that these terms differ, but it looks like that aggressiveness of vacuum refers only to freezing, because if there are any dead tuples on page we visit it anyway -- which makes it even more confusing. Perhaps things can be improved here, e.g. coin 'agressive freezing' everywhere and explicitly say in FREEZE docs that it additionaly ignores vacuum_freeze_min_age? Or I just misunderstand something. [1] https://www.postgresql.org/docs/devel/static/routine-vacuuming.html [2] https://www.postgresql.org/docs/devel/static/sql-vacuum.html -- Arseny Sher Postgres Professional: http://www.postgrespro.com The Russian Postgres Company