X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by postgresql.org (Postfix) with ESMTP id 8ADC19DCC30 for ; Thu, 26 Jan 2006 21:55:52 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 22025-02-2 for ; Thu, 26 Jan 2006 21:55:56 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey- Received: from smtpauth04.mail.atl.earthlink.net (smtpauth04.mail.atl.earthlink.net [209.86.89.64]) by postgresql.org (Postfix) with ESMTP id 8A76D9DCC10 for ; Thu, 26 Jan 2006 21:55:49 -0400 (AST) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=dk20050327; d=earthlink.net; b=aqi4xk+ix+r20QJxwS/n62XmYF/XB1nHsKGI0utwM7myGRuGVSrP7+u/f3+v/+Kg; h=Received:Message-Id:X-Mailer:Date:To:From:Subject:In-Reply-To:References:Mime-Version:Content-Type:X-ELNK-Trace:X-Originating-IP; Received: from [70.22.189.241] (helo=ron-6d52adff2a6.earthlink.net) by smtpauth04.mail.atl.earthlink.net with asmtp (Exim 4.34) id 1F2Iq8-00019V-T3; Thu, 26 Jan 2006 20:55:53 -0500 Message-Id: <7.0.1.0.2.20060126202809.03838ab0@earthlink.net> X-Mailer: QUALCOMM Windows Eudora Version 7.0.1.0 Date: Thu, 26 Jan 2006 20:55:46 -0500 To: Alvaro Herrera , pgsql-performance@postgresql.org From: Ron Subject: Re: [GENERAL] Creation of tsearch2 index is very In-Reply-To: <20060127010054.GD13501@surnet.cl> References: <20060120213754.GG31908@svana.org> <7.0.1.0.2.20060120174141.039b03e8@earthlink.net> <6111.1137797436@sss.pgh.pa.us> <20060120225751.GA27230@uio.no> <6532.1137801157@sss.pgh.pa.us> <20060121000519.GA29755@uio.no> <6743.1137802990@sss.pgh.pa.us> <7.0.1.0.2.20060121064930.03aba810@earthlink.net> <18771.1137868073@sss.pgh.pa.us> <7.0.1.0.2.20060126190219.0388a918@earthlink.net> <20060127010054.GD13501@surnet.cl> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; format=flowed X-ELNK-Trace: acd68a6551193be5d780f4a490ca69563f9fea00a6dd62bc94879345c8970e4509a5c572567efd7c350badd9bab72f9c350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 70.22.189.241 X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, score=0.438 required=5 tests=[AWL=-0.041, DNS_FROM_RFC_ABUSE=0.479] X-Spam-Score: 0.438 X-Spam-Level: X-Archive-Number: 200601/453 X-Sequence-Number: 16931 At 08:00 PM 1/26/2006, Alvaro Herrera wrote: >Ron wrote: > > At 01:27 PM 1/21/2006, Tom Lane wrote: > > >Ron writes: > > >> At 07:23 PM 1/20/2006, Tom Lane wrote: > > >>> Well, we're trying to split an index page that's gotten full into > > >>> two index pages, preferably with approximately equal numbers > of items in > > >>> each new page (this isn't a hard requirement though). > > > After reading the various papers available on GiST and RD trees, I > > think I have a decent suggestion. > >I for one don't understand what does your suggestion have to do with the >problem at hand ... not that I have a better one myself. We have two problems here. The first is that the page splitting code for these indexes currently has O(N^2) performance. The second is that whatever solution we do use for this functionality, we still need good performance during searches that use the index. It's not clear that the solutions we've discussed to splitting index pages thus far will result in good performance during searches. My suggestion is intended to address both issues. If I'm right it helps obtain high performance during searches while allowing the index page splitting code to be O(1) Ron.