Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1Tt6AQ-0002lz-A4 for pgsql-hackers@arkaria.postgresql.org; Thu, 10 Jan 2013 00:38:46 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.72) (envelope-from ) id 1Tt6AP-0001Zg-Gp for pgsql-hackers@arkaria.postgresql.org; Thu, 10 Jan 2013 00:38:45 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1Tt6AO-0001Zb-Nq for pgsql-hackers@postgresql.org; Thu, 10 Jan 2013 00:38:44 +0000 Received: from outmail149061.authsmtp.co.uk ([62.13.149.61]) by magus.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1Tt6AM-0005hd-Dl for pgsql-hackers@postgresql.org; Thu, 10 Jan 2013 00:38:44 +0000 Received: from mail-c226.authsmtp.com (mail-c226.authsmtp.com [62.13.128.226]) by punt9.authsmtp.com (8.14.2/8.14.2/Kp) with ESMTP id r0A0cenb055888 for ; Thu, 10 Jan 2013 00:38:40 GMT Received: from [192.168.1.102] (50-0-190-199.dsl.dynamic.sonic.net [50.0.190.199]) (authenticated bits=0) by mail.authsmtp.com (8.14.2/8.14.2/) with ESMTP id r0A0cbgm098697 for ; Thu, 10 Jan 2013 00:38:38 GMT Message-ID: <50EE0D8C.3080602@agliodbs.com> Date: Wed, 09 Jan 2013 16:38:36 -0800 From: Josh Berkus Organization: PostgreSQL Experts Inc. User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: pgsql-hackers@postgresql.org Subject: Re: 9.2.1 & index-only scans : abnormal heap fetches after VACUUM FULL References: <20130109230731.GA30885@momjian.us> In-Reply-To: <20130109230731.GA30885@momjian.us> X-Enigmail-Version: 1.4.6 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Server-Quench: 1309f99c-5abe-11e2-98a9-0025907ec6c5 X-AuthReport-Spam: If SPAM / abuse - report it at: http://www.authsmtp.com/abuse X-AuthRoute: OCdyZgscClZXSx8a IioLCC5HRQ8+YBZL BAkbIhBDJB8JXA9S P1xBBkJUK0ETX1xC QjoVBBYDHlxxRhkk NRVTbQReckpOVQZi WktBDFdSCgV2ABUB GB8XWwZwdBpGNjxw FEYxDCcGXE1yc096 DE9UEWRIZGRgYTYW WRNFclIGJR5Lf0pH d1l3BXoQYWUFY3Ng QAI4YTtsKw9Semxm YigmDn8oenNDT3hm AUlKU30uG0EIV2A0 KRg3YkUXFUAKehd6 OFEnXkgdOhtaCgBX BwlDDTNSJ1QaDyMl EQ5APwYgORZgfAIU LCAMBncA X-Authentic-SMTP: 61633136333939.1020:706 X-AuthFastPath: 0 (Was 255) X-AuthSMTP-Origin: 50.0.190.199/23 X-AuthVirus-Status: No virus detected - but ensure you scan with your own anti-virus system. X-Pg-Spam-Score: -2.6 (--) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-hackers Precedence: bulk Sender: pgsql-hackers-owner@postgresql.org On 01/09/2013 03:07 PM, Bruce Momjian wrote: > How do we want to handle the case where VACUUM FULL clears the > visibility map, causing loss of index-only scans? > > http://archives.postgresql.org/pgsql-performance/2012-11/msg00317.php > > Do we document this behavior or add a TODO item? > Both? Surely VACUUM FULL should rebuild the visibility map, and make tuples in the new relation all-visible, no? -- Josh Berkus PostgreSQL Experts Inc. http://pgexperts.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers