Received: from maia.hub.org (maia-2.hub.org [200.46.204.251]) by mail.postgresql.org (Postfix) with ESMTP id B0DA41337B2F for ; Thu, 3 Feb 2011 12:23:08 -0400 (AST) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.251]) (amavisd-maia, port 10024) with ESMTP id 86761-03 for ; Thu, 3 Feb 2011 16:23:01 +0000 (UTC) X-Greylist: delayed 00:06:42.620274 by SQLgrey-1.7.6 Received: from tanagra.summersault.com (tanagra.summersault.com [12.161.105.149]) by mail.postgresql.org (Postfix) with ESMTP id 2674C133740B for ; Thu, 3 Feb 2011 12:23:01 -0400 (AST) Received: (qmail 30236 invoked from network); 3 Feb 2011 16:16:15 -0000 Received: from simba.summersault.com (192.168.97.182) by tanagra.summersault.com with SMTP; 3 Feb 2011 16:16:15 -0000 Message-ID: <4D4AD4CF.5060702@summersault.com> Date: Thu, 03 Feb 2011 11:16:15 -0500 From: Mark Stosberg User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.13) Gecko/20101208 Thunderbird/3.1.7 MIME-Version: 1.0 CC: pgsql-performance@postgresql.org Subject: Re: getting the most of out multi-core systems for repeated complex SELECT statements References: In-Reply-To: X-Enigmail-Version: 1.1.1 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-0.889 tagged_above=-10 required=5 tests=BAYES_00=-1.9, MISSING_HEADERS=1.021, T_RP_MATCHES_RCVD=-0.01 X-Spam-Level: X-Archive-Number: 201102/83 X-Sequence-Number: 42221 On 02/03/2011 10:54 AM, Oleg Bartunov wrote: > Mark, > > you could try gevel module to get structure of GIST index and look if > items distributed more or less homogenous (see different levels). You > can visualize index like http://www.sai.msu.su/~megera/wiki/Rtree_Index > Also, if your searches are neighbourhood searches, them you could try > knn, available > in 9.1 development version. Oleg, Those are interesting details to consider. I read more about KNN here: http://www.depesz.com/index.php/2010/12/11/waiting-for-9-1-knngist/ Will I be able to use it improve the performance of finding nearby zipcodes? It sounds like KNN has great potential for performance improvements! Mark