Received: from maia.hub.org (unknown [200.46.208.211]) by mail.postgresql.org (Postfix) with ESMTP id DD7996340AD for ; Tue, 2 Feb 2010 14:38:39 -0400 (AST) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.208.211]) (amavisd-maia, port 10024) with ESMTP id 56843-04 for ; Tue, 2 Feb 2010 18:38:18 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from spinlock.commandprompt.com (host-215.commandprompt.net [207.173.203.215]) by mail.postgresql.org (Postfix) with ESMTP id 607A363F4D5 for ; Tue, 2 Feb 2010 13:16:00 -0400 (AST) Received: from perhan.alvh.no-ip.org (190-95-21-56.bk17-dsl.surnet.cl [190.95.21.56]) by spinlock.commandprompt.com (Postfix) with ESMTPSA id 28DAB348041; Tue, 2 Feb 2010 08:20:48 -0800 (PST) Received: by perhan.alvh.no-ip.org (Postfix, from userid 1000) id 469D86E64D; Tue, 2 Feb 2010 13:20:46 -0300 (CLST) Date: Tue, 2 Feb 2010 13:20:46 -0300 From: Alvaro Herrera To: Scott Marlowe Cc: wyx6fox@sina.com, pgsql-performance@postgresql.org Subject: Re: the jokes for pg concurrency write performance Message-ID: <20100202162046.GA4020@alvh.no-ip.org> References: <20100202045701.93A404B1C73@mail175-236.sinamail.sina.com.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-2.542 tagged_above=-10 required=5 tests=AWL=0.057, BAYES_00=-2.599 X-Spam-Level: X-Archive-Number: 201002/12 X-Sequence-Number: 37433 Scott Marlowe escribió: > 2010/2/1 : > Let's rewrite this assertion: > > * joke 1: insert operation would use a excluse lock on reference row by the > > foreign key . a big big big performance killer , i think this is a stupid > > design . > > "problem #1: insert operation would use a excluse lock on reference row by the > foreign key . a big big big performance killer. " Yeah, if it had been written this way I could have told him that this is not the case since 8.1, but since he didn't, I simply skipped his emails. -- Alvaro Herrera http://www.CommandPrompt.com/ The PostgreSQL Company - Command Prompt, Inc.