Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1Tfxde-0006SI-UR for pgsql-performance@arkaria.postgresql.org; Tue, 04 Dec 2012 18:54:39 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.72) (envelope-from ) id 1Tfxde-0002WN-FJ for pgsql-performance@arkaria.postgresql.org; Tue, 04 Dec 2012 18:54:38 +0000 Received: from makus.postgresql.org ([98.129.198.125]) by malur.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1Tfxdd-0002WI-M8 for pgsql-performance@postgresql.org; Tue, 04 Dec 2012 18:54:37 +0000 Received: from li188-192.members.linode.com ([178.79.132.192] helo=foo.me.uk) by makus.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1Tfxdc-0002dz-M4 for pgsql-performance@postgresql.org; Tue, 04 Dec 2012 18:54:37 +0000 Received: from webmail.cantabcapital.com ([212.44.17.222] helo=CCPPRT350008) by foo.me.uk with esmtpa (Exim 4.71) (envelope-from ) id 1Tfxx3-0001KZ-Uf for pgsql-performance@postgresql.org; Tue, 04 Dec 2012 19:14:42 +0000 From: To: "'postgres performance list'" References: <092a01cdd230$ff6143c0$fe23cb40$@foo.me.uk> <098101cdd24d$892524c0$9b6f6e40$@foo.me.uk> In-Reply-To: Date: Tue, 4 Dec 2012 18:54:29 -0000 Message-ID: <098601cdd250$ce2f85d0$6a8e9170$@foo.me.uk> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook 14.0 Thread-Index: AQE7bKfasxp9xMk0I5yxURpgMQ+bBAG7NE8VAkUnRdQCz7DsFJj3R3Bg Content-Language: en-gb X-SA-Exim-Connect-IP: 212.44.17.222 X-SA-Exim-Mail-From: pscott@foo.me.uk X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on foo.me.uk X-Spam-Level: X-Spam-Status: No, score=-2.9 required=5.0 tests=ALL_TRUSTED,BAYES_00 autolearn=ham version=3.3.1 Subject: Re: Slow query: bitmap scan troubles X-SA-Exim-Version: 4.2.1 (built Sat, 07 Nov 2009 20:03:47 +0000) X-SA-Exim-Scanned: Yes (on foo.me.uk) X-Pg-Spam-Score: -1.9 (-) 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 Ah, okay - my reasoning was there's a big fancy-pants raid array behind it that makes disk operations faster relative to CPU ones. I'll test it and see if it actually makes any difference. -----Original Message----- From: Claudio Freire [mailto:klaussfreire@gmail.com] Sent: 04 December 2012 18:33 To: Philip Scott Cc: postgresql@foo.me.uk; postgres performance list Subject: Re: [PERFORM] Slow query: bitmap scan troubles On Tue, Dec 4, 2012 at 3:31 PM, Philip Scott wrote: > r_p_c 2-> 1 (s_p_c 1->0.5): Is this really necessary? (looks like a no-op, unless your CPU is slow) -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance