From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id o4RBjFlK130603 for ; Thu, 27 May 2010 06:45:15 -0500 Received: from bombadil.infradead.org (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 99F7F157B50C for ; Thu, 27 May 2010 04:49:29 -0700 (PDT) Received: from bombadil.infradead.org (bombadil.infradead.org [18.85.46.34]) by cuda.sgi.com with ESMTP id GOPxVlydcJ3PiNtz for ; Thu, 27 May 2010 04:49:29 -0700 (PDT) Date: Thu, 27 May 2010 07:47:37 -0400 From: Christoph Hellwig Subject: Re: NOW: o_direct -- WAS: Re: WARNING in xfs_lwr.c, xfs_write() Message-ID: <20100527114736.GA13112@infradead.org> References: <20100523002023.41f5a5c8@aaa.pulp.binarylife.net> <20100523101856.GL2150@dastard> <20100523092344.0fcaab42@aaa.pulp.binarylife.net> <4BF9FCA8.8090906@hardwarefreak.com> <20100524143428.6f3a117c@abend.internal.xtremedata.com> <20100526070620.GT2150@dastard> <4BFD3926.6040208@hardwarefreak.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <4BFD3926.6040208@hardwarefreak.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Stan Hoeppner Cc: xfs@oss.sgi.com O_DIRECT is not a Posix standard and not very portable. It originated on IRIX, and Linux inherited it during the 2.4 kernel series days. These days FreeBSD/NetBSD and AIX support it as well, but for example Solaris, HP-UX and OpenBSD don't, nevermind Windows or Mac OS. I have no idea why the MTAs don't want to use it - it's generally easier to use then memory mapped I/O, and has much more deterministic performance. _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs