From: Trond Myklebust Subject: Re: NFS_UNSTABLE vs. FILE and DATA sync. Date: Mon, 06 Aug 2007 14:58:30 -0400 Message-ID: <1186426710.6616.57.camel@localhost> References: <46B74E5C.4060400@oracle.com> <46B755FE.1010909@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Cc: nfs@lists.sourceforge.net, Wim Colgate To: chuck.lever@oracle.com Return-path: Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.92] helo=mail.sourceforge.net) by sc8-sf-list2-new.sourceforge.net with esmtp (Exim 4.43) id 1II7mo-0003Sw-PB for nfs@lists.sourceforge.net; Mon, 06 Aug 2007 11:58:39 -0700 Received: from pat.uio.no ([129.240.10.15] ident=[U2FsdGVkX19KYs08YBljbzjsuZxZb6u+ILhtc57IC2o=]) by mail.sourceforge.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.44) id 1II7mq-00054X-BC for nfs@lists.sourceforge.net; Mon, 06 Aug 2007 11:58:43 -0700 In-Reply-To: <46B755FE.1010909@oracle.com> List-Id: "Discussion of NFS under Linux development, interoperability, and testing." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: nfs-bounces@lists.sourceforge.net Errors-To: nfs-bounces@lists.sourceforge.net On Mon, 2007-08-06 at 13:10 -0400, Chuck Lever wrote: > Even though an NFS client requests an NFS_FILE_SYNC write, the server > still has the choice of returning something less, even NFS_UNSTABLE. In > general that's a rare occurrence, but is something I've seen in practice. As Peter said, a server that return anything other than FILE_SYNC to a FILE_SYNC write request would be in clear violation of the description of WRITE semantics on page 51 of RFC1813: committed The server should return an indication of the level of commitment of the data and metadata via committed. If the server committed all data and metadata to stable storage, committed should be set to FILE_SYNC. If the level of commitment was at least as strong as DATA_SYNC, then committed should be set to DATA_SYNC. Otherwise, committed must be returned as UNSTABLE. If stable was FILE_SYNC, then committed must also be FILE_SYNC: anything else constitutes a protocol violation. If stable was DATA_SYNC, then committed may be FILE_SYNC or DATA_SYNC: anything else constitutes a protocol violation. If stable was UNSTABLE, then committed may be either FILE_SYNC, DATA_SYNC, or UNSTABLE. I see no reason why we should care about supporting such a server. Trond ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs