X-Original-To: pgsql-hackers-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.2]) by svr1.postgresql.org (Postfix) with ESMTP id B2AACD1B4E8 for ; Wed, 15 Oct 2003 21:03:02 +0000 (GMT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (neptune.hub.org [200.46.204.2]) (amavisd-new, port 10024) with ESMTP id 33832-05 for ; Wed, 15 Oct 2003 18:02:33 -0300 (ADT) Received: from trolak.mydnsbox2.com (ns1.mydnsbox2.com [207.44.142.118]) by svr1.postgresql.org (Postfix) with ESMTP id 56EAED1B4F1 for ; Wed, 15 Oct 2003 18:02:30 -0300 (ADT) Received: from dunslane.net (x.ncshp.org [199.90.235.43]) (authenticated (0 bits)) by trolak.mydnsbox2.com (8.11.6/8.11.6) with ESMTP id h9FKuXH08315 for ; Wed, 15 Oct 2003 15:56:33 -0500 Message-ID: <3F8DB5D7.1060600@dunslane.net> Date: Wed, 15 Oct 2003 17:02:15 -0400 From: Andrew Dunstan User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/20030703 X-Accept-Language: en-us, en MIME-Version: 1.0 Cc: pgsql-hackers@postgresql.org Subject: Re: Database Kernels and O_DIRECT References: <15890.1066232585@sss.pgh.pa.us> In-Reply-To: <15890.1066232585@sss.pgh.pa.us> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: by amavisd-new at postgresql.org X-Archive-Number: 200310/753 X-Sequence-Number: 45435 Tom Lane wrote: >James Rogers writes: > > >>If we suddenly wanted to optimize Postgres for performance the way >>Oracle does, we would be a lot more keen on the O_DIRECT approach. >> >> > >This isn't ever going to happen, for the simple reason that we don't >have Oracle's manpower. > [snip - long and sensible elaboration of above statement] I have wondered (somewhat fruitlessly) for several years about the possibilities of special purpose lightweight file systems that could relax some of the assumptions and checks used in general purpose file systems. Such a thing might provide most of the benefits of a "database kernel" without imposing anything extra on the database application layer. Just a thought - I have no resources to make any attack on such a project. cheers andrew