Received: from maia.hub.org (maia-2.hub.org [200.46.204.251]) by mail.postgresql.org (Postfix) with ESMTP id DEE83B5DC59 for ; Wed, 13 Jul 2011 05:33:31 -0300 (ADT) 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 96918-04 for ; Wed, 13 Jul 2011 08:33:25 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from exprod7og102.obsmtp.com (exprod7og102.obsmtp.com [64.18.2.157]) by mail.postgresql.org (Postfix) with ESMTP id E6D2AB5DC63 for ; Wed, 13 Jul 2011 05:33:24 -0300 (ADT) Received: from mail-fx0-f42.google.com ([209.85.161.42]) (using TLSv1) by exprod7ob102.postini.com ([64.18.6.12]) with SMTP ID DSNKTh1YU5rhKe4LZ+JsAL6FUe4Oi48dmQF2@postini.com; Wed, 13 Jul 2011 01:33:25 PDT Received: by fxe23 with SMTP id 23so7434327fxe.29 for ; Wed, 13 Jul 2011 01:33:22 -0700 (PDT) Received: by 10.223.96.198 with SMTP id i6mr1357028fan.22.1310546002103; Wed, 13 Jul 2011 01:33:22 -0700 (PDT) Received: from [192.168.1.183] (dsl-hkibrasgw2-ff7ac300-240.dhcp.inet.fi [88.195.122.240]) by mx.google.com with ESMTPS id 21sm10260280fay.21.2011.07.13.01.33.18 (version=TLSv1/SSLv3 cipher=OTHER); Wed, 13 Jul 2011 01:33:19 -0700 (PDT) Message-ID: <4E1D584D.2070706@enterprisedb.com> Date: Wed, 13 Jul 2011 11:33:17 +0300 From: Heikki Linnakangas User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; fi-FI; rv:1.9.2.18) Gecko/20110626 Icedove/3.1.11 MIME-Version: 1.0 To: Alexander Korotkov CC: pgsql-hackers Subject: Re: WIP: Fast GiST index build References: <4DF8676F.9040801@enterprisedb.com> <4DFA4AE5.1010806@enterprisedb.com> <4E044D68.5070605@enterprisedb.com> <4E0894FF.8080202@enterprisedb.com> <26338.1310134685@sss.pgh.pa.us> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-1.9 tagged_above=-5 required=5 tests=BAYES_00=-1.9 X-Spam-Level: X-Archive-Number: 201107/652 X-Sequence-Number: 191751 Hi, Looking at the performance test results again on the wiki page (http://wiki.postgresql.org/wiki/Fast_GiST_index_build_GSoC_2011#Testing_results), the patch can be summarized like this: it reduces the number of disk accesses, at the cost of some extra CPU work. Is it possible to switch to the new buffering method in the middle of an index build? We could use the plain insertion method until the index grows to a certain size (effective_cache_size?), and switch to the buffering method after that. -- Heikki Linnakangas EnterpriseDB http://www.enterprisedb.com