From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id o3R9Uvgd149868 for ; Tue, 27 Apr 2010 04:30:57 -0500 Received: from enyo.dsw2k3.info (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 7A4732F4653 for ; Tue, 27 Apr 2010 02:33:00 -0700 (PDT) Received: from enyo.dsw2k3.info (enyo.dsw2k3.info [195.71.86.239]) by cuda.sgi.com with ESMTP id jnOKIyERa4CYUnEN for ; Tue, 27 Apr 2010 02:33:00 -0700 (PDT) Date: Tue, 27 Apr 2010 11:32:50 +0200 From: Matthias Schniedermeyer Subject: Re: O_SYNC behavior? Message-ID: <20100427093250.GA15182@citd.de> References: <20100426225627.GA7106@esri.com> <537687191.239471272324343715.JavaMail.root@mail-au.aconex.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <537687191.239471272324343715.JavaMail.root@mail-au.aconex.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: Nathan Scott Cc: xfs@oss.sgi.com, Ray Van Dolson On 27.04.2010 09:25, Nathan Scott wrote: > > ----- "Ray Van Dolson" wrote: > > > End-user question: > > > > NFS client accessing an NFS export on an XFS based filesystem via > > "sync" (O_SYNC) mode. > > > > Will write confirmation be sent back from the NFS server when the > > data is written to the xfs journal, > > Data is never written to the journal. I don't think that answers the intented question. I guess the correct answer is: It depends on the server-side configuration. An "async" export gets the "done"-answer immediatly. An "sync" export (only when also mounted "sync" AFAIU) waits at least until the write command is send down the stack, maybe even until the data actually hit the platters or silicon in the SSD-case. man 5 exports: - snip - sync: Reply to requests only after the changes have been committed to stable storage - snip - But i guess the performance will be horrible when both side are "sync". Bis denn -- Real Programmers consider "what you see is what you get" to be just as bad a concept in Text Editors as it is in women. No, the Real Programmer wants a "you asked for it, you got it" text editor -- complicated, cryptic, powerful, unforgiving, dangerous. _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs