From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754248Ab1ASQnY (ORCPT ); Wed, 19 Jan 2011 11:43:24 -0500 Received: from rcsinet10.oracle.com ([148.87.113.121]:40295 "EHLO rcsinet10.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753751Ab1ASQnX convert rfc822-to-8bit (ORCPT ); Wed, 19 Jan 2011 11:43:23 -0500 MIME-Version: 1.0 Message-ID: Date: Wed, 19 Jan 2011 08:42:26 -0800 (PST) From: Dan Magenheimer To: Andrew Morton Cc: torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, Christoph Hellwig , Jeremy Fitzhardinge Subject: RE: Ping? RE: [GIT PULL] mm/vfs/fs:cleancache for 2.6.37 merge window References: <7b34b3ea-9436-4077-a35e-a5eaabd59813@default 20101030120632.40345d0d.akpm@linux-foundation.org> In-Reply-To: <20101030120632.40345d0d.akpm@linux-foundation.org> X-Priority: 3 X-Mailer: Oracle Beehive Extensions for Outlook 2.0.1.4.1.0 (410211) [OL 12.0.6539.5000] Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Wed, 27 Oct 2010 11:37:47 -0700 (PDT) Dan Magenheimer > wrote: > > > Ping? I hope you are still considering this. If not or if > > there are any questions I can answer, please let me know. > > What's happened here is that the patchset has gone through its > iterations and a few people have commented and then after a while, > nobody had anything to say about the code so nobody said anything more. > > But silence doesn't mean acceptance - it just means that nobody had > anything to say. > > I think I looked at the earlier iterations, tried to understand the > point behind it all, made a few code suggestions and eventually tuned > out. At that time (and hence at this time) I just cannot explain to > myself why we would want to merge this code. > > All new code is a cost/benefit decision. The costs are pretty well > known: larger codebase, more code for us and our "customers" to > maintain and support, etc. That the code pokes around in vfs and > various filesystems does increase those costs a little. > > But the extent of the benefits to our users aren't obvious to me. The > coe is still xen-specific, I believe? If so, that immediately reduces > the benefit side by a large amount simply because of the reduced > audience. > > We did spend some time trying to get this wired up to zram so that the > feature would be potentially useful to *all* users, thereby setting the > usefulness multiplier back to 1.0. But I don't recall that anything > came of this? > > I also don't know how useful the code is to its intended > micro-audience: xen users! > > So can we please revisit all this from the top level? Jeremy, your > input would be valuable. Christoph, I recall that you had technical > objections - can you please repeat those? > > It's the best I can do to kick this along, sorry. Hi Andrew (and Linus) -- Time to re-open this conversation (for 2.6.39 merge window)? Assuming GregKH approves kztmem as a staging driver, it should now set "the usefulness multiplier back to 1.0". Kztmem is a superset of Nitin's zcache and zram but more dynamic and is completely independent of Xen and virtualization. See kztmem overview: https://lkml.org/lkml/2011/1/18/170 And I believe Christoph's technical objections have all been resolved. See longer version of previous reply here: https://lkml.org/lkml/2010/10/30/226 So please reconsider cleancache! Thanks, Dan P.S. Christoph, apologies, I see I didn't have you on the dist list for the kztmem patch.