Return-Path: linux-nfs-owner@vger.kernel.org Received: from mx2.netapp.com ([216.240.18.37]:27027 "EHLO mx2.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753029Ab1K1PmQ convert rfc822-to-8bit (ORCPT ); Mon, 28 Nov 2011 10:42:16 -0500 Message-ID: <1322494933.6125.21.camel@lade.trondhjem.org> Subject: Re: [PATCH] NFSV4 :All lock operations should be sent to the server for resolution From: Trond Myklebust To: Mi Jinlong Cc: "J. Bruce Fields" , linux-nfs@vger.kernel.org Date: Mon, 28 Nov 2011 10:42:13 -0500 In-Reply-To: <4ED32AAB.8010800@cn.fujitsu.com> References: <4D2FF124.7020500@cn.fujitsu.com> <20110114181600.GA15352@fieldses.org> <1295029762.3576.9.camel@heimdal.trondhjem.org> <4ED32AAB.8010800@cn.fujitsu.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-nfs-owner@vger.kernel.org List-ID: On Mon, 2011-11-28 at 14:31 +0800, Mi Jinlong wrote: > Hi Trond, > > Trond Myklebust: > > The ability to cache locks is one of the main reasons for holding > > delegations in the first place. Sure, the spec allows for non-posix > > locking, but the Linux client doesn't. > > Would you mind tell me some about why we not support non-posix locking at NFS ? For the very obvious reason that Linux applications are coded under the assumption that the kernel implements POSIX locking semantics. Why would we want to implement support for NFS features that can cause perfectly correctly coded applications to hang and crash? Trond -- Trond Myklebust Linux NFS client maintainer NetApp Trond.Myklebust@netapp.com www.netapp.com