Received: from maia.hub.org (maia-5.hub.org [200.46.204.29]) by mail.postgresql.org (Postfix) with ESMTP id 1EECBB5DC09 for ; Tue, 20 Sep 2011 15:09:57 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.29]) (amavisd-maia, port 10024) with ESMTP id 02024-02 for ; Tue, 20 Sep 2011 18:09:50 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0-rc2 Received: from smtp-out-2.01.com (smtp.01.com [216.115.88.169]) by mail.postgresql.org (Postfix) with ESMTP id A2435B5DC00 for ; Tue, 20 Sep 2011 15:09:50 -0300 (ADT) Received: from localhost (localhost.localdomain [127.0.0.1]) by smtp-out-2.01.com (Postfix) with ESMTP id BA60E41411E for ; Tue, 20 Sep 2011 13:09:49 -0500 (CDT) X-Virus-Scanned: amavisd-new at smtp-out-2.01.com Received: from smtp-out-2.01.com ([127.0.0.1]) by localhost (smtp-out-2.01.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id VgTF6nrTfEDA for ; Tue, 20 Sep 2011 13:09:49 -0500 (CDT) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp-out-2.01.com (Postfix) with ESMTP id 9A9E8414130 for ; Tue, 20 Sep 2011 13:09:49 -0500 (CDT) Received: from Sidney-Stratton.local (70-36-143-92.dsl.dynamic.sonic.net [70.36.143.92]) by smtp-out-2.01.com (Postfix) with ESMTPSA id 74A91414124 for ; Tue, 20 Sep 2011 13:09:49 -0500 (CDT) Message-ID: <4E78D6EC.30205@agliodbs.com> Date: Tue, 20 Sep 2011 11:09:48 -0700 From: Josh Berkus Organization: PostgreSQL Experts Inc. User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.2.15) Gecko/20110303 Lightning/1.0b2 Thunderbird/3.1.9 MIME-Version: 1.0 To: pgsql-performance@postgresql.org Subject: Re: : Performance Improvement Strategy References: In-Reply-To: X-Enigmail-Version: 1.1.1 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-1.899 tagged_above=-10 required=5 tests=BAYES_00=-1.9, TO_NO_BRKTS_PCNT=0.001 X-Spam-Level: X-Archive-Number: 201109/291 X-Sequence-Number: 45067 Venkat, > I see lot of free spaces or free pages in Tables and Indexes. But, I need to > give an exact calculation on how much space will be reclaimed after VACUUM > FULL and RE-INDEXING. At present, there is no way to calculate this precisely. You can only estimate, and estimates have significant error factors. The query which Marcin linked for you, for example, can be as much as 500% off (although usually only 50% off). -- Josh Berkus PostgreSQL Experts Inc. http://pgexperts.com