X-Original-To: pgsql-performance-postgresql.org@postgresql.org Received: from localhost (wm.hub.org [200.46.204.128]) by postgresql.org (Postfix) with ESMTP id C3C549FB2D9 for ; Thu, 21 Sep 2006 16:42:07 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.128]) (amavisd-new, port 10024) with ESMTP id 03344-02 for ; Thu, 21 Sep 2006 19:41:58 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey- Received: from mir3-fs.mir3.com (mail.mir3.com [65.208.188.100]) by postgresql.org (Postfix) with ESMTP id 713CE9FB227 for ; Thu, 21 Sep 2006 16:41:58 -0300 (ADT) Received: mir3-fs.mir3.com 172.16.1.11 from 172.16.2.68 172.16.2.68 via HTTP with MS-WebStorage 6.0.6249 Received: from archimedes.mirlogic.com by mir3-fs.mir3.com; 21 Sep 2006 12:41:54 -0700 Subject: Re: Large tables (was: RAID 0 not as fast as From: Mark Lewis To: Bucky Jordan Cc: Luke Lonergan , Markus Schaber , pgsql-performance@postgresql.org In-Reply-To: <78ED28FACE63744386D68D8A9D1CF5D4209A6E@MAIL.corp.lumeta.com> References: <78ED28FACE63744386D68D8A9D1CF5D4209A6E@MAIL.corp.lumeta.com> Content-Type: text/plain Content-Transfer-Encoding: 7bit Organization: MIR3, Inc. Date: Thu, 21 Sep 2006 12:41:54 -0700 Message-Id: <1158867714.9657.1680.camel@archimedes> Mime-Version: 1.0 X-Mailer: Evolution 2.0.2 (2.0.2-27) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0.001 tagged_above=0 required=5 tests=UNPARSEABLE_RELAY X-Spam-Level: X-Archive-Number: 200609/284 X-Sequence-Number: 20970 > So this might be a dumb question, but the above statements apply to the > cluster (e.g. postmaster) as a whole, not per postgres > process/transaction correct? So each transaction is blocked waiting for > the main postmaster to retrieve the data in the order it was requested > (i.e. not multiple scanners/aio)? Each connection runs its own separate back-end process, so these statements apply per PG connection (=process).