Return-Path: linux-nfs-owner@vger.kernel.org Received: from mx2.netapp.com ([216.240.18.37]:42391 "EHLO mx2.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757217Ab1K3AIM convert rfc822-to-8bit (ORCPT ); Tue, 29 Nov 2011 19:08:12 -0500 Message-ID: <1322611689.11286.72.camel@lade.trondhjem.org> Subject: Re: [PATCH 0/4] nfs41: allow layoutget at pnfs_do_multiple_writes From: Trond Myklebust To: Marc Eshel Cc: Peng Tao , bhalevy@tonian.com, Boaz Harrosh , Garth Gibson , Fred Isaman , linux-nfs@vger.kernel.org, Matt Benjamin Date: Tue, 29 Nov 2011 19:08:09 -0500 In-Reply-To: References: <1322887965-2938-1-git-send-email-bergwolf@gmail.com> <4ED54FE4.9050008@panasas.com> <4ED55399.4060707@panasas.com> <1322603848.11286.7.camel@lade.trondhjem.org> <4ED55F78.205@panasas.com> <1322606842.11286.33.camel@lade.trondhjem.org> <4ED563AC.5040501@panasas.com> <1322609431.11286.56.camel@lade.trondhjem.org> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-nfs-owner@vger.kernel.org List-ID: On Tue, 2011-11-29 at 15:49 -0800, Marc Eshel wrote: > The only 1 cent that I can add to this argument is that I was led to > believe by you and others that Linux kernel don't add functionality on the > client side that is not supported on the server side. Last time I made > this point I was told that it is ok if they are of by a version or two. > You made it clear that this is no longer true and that the Linux client > and server are now independent of each other. I spent time working on the > server side believing that the client and server will progress more or > less together, disappointed to find out that it is not the case any more. > Marc. I don't know how to manage layout segments in a way that meets the pNFS goals of scalability and performance, and neither you nor the pNFS spec have told me how to do this. If IBM wants a client that implements layout segments, then it is _your_ responsibility to: A. Convince me that it is an implementable part of the spec. B. Provide me with an implementation that deals all with the concerns that I have. IOW: nobody has ever promised IBM that the community would do all your client work for you. EMC, NetApp and Panasas have implemented (most of) the bits that they cared about; any bits that they haven't implemented and that you care about are up to you. -- Trond Myklebust Linux NFS client maintainer NetApp Trond.Myklebust@netapp.com www.netapp.com