From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755914Ab1KASuG (ORCPT ); Tue, 1 Nov 2011 14:50:06 -0400 Received: from e3.ny.us.ibm.com ([32.97.182.143]:33287 "EHLO e3.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754587Ab1KASuD (ORCPT ); Tue, 1 Nov 2011 14:50:03 -0400 Subject: RE: [GIT PULL] mm: frontswap (for 3.2 window) From: Dave Hansen To: Dan Magenheimer Cc: James Bottomley , John Stoffel , Johannes Weiner , Pekka Enberg , Cyclonus J , Sasha Levin , Christoph Hellwig , David Rientjes , Linus Torvalds , linux-mm@kvack.org, LKML , Andrew Morton , Konrad Wilk , Jeremy Fitzhardinge , Seth Jennings , ngupta@vflare.org, Chris Mason , JBeulich@novell.com, Jonathan Corbet In-Reply-To: References: <75efb251-7a5e-4aca-91e2-f85627090363@default> <20111027215243.GA31644@infradead.org> <1319785956.3235.7.camel@lappy> <552d2067-474d-4aef-a9a4-89e5fd8ef84f@default> <20111028163053.GC1319@redhat.com> <20138.62532.493295.522948@quad.stoffel.home> <3982e04f-8607-4f0a-b855-2e7f31aaa6f7@default> <1320048767.8283.13.camel@dabdike> <424e9e3a-670d-4835-914f-83e99a11991a@default 1320142403.7701.62.camel@dabdike> Content-Type: text/plain; charset="UTF-8" Date: Tue, 01 Nov 2011 11:48:14 -0700 Message-ID: <1320173294.15403.109.camel@nimitz> Mime-Version: 1.0 X-Mailer: Evolution 2.32.2 Content-Transfer-Encoding: 7bit x-cbid: 11110118-8974-0000-0000-000001520E24 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2011-11-01 at 11:10 -0700, Dan Magenheimer wrote: > Case A) CONFIG_FRONTSWAP=n > Case B) CONFIG_FRONTSWAP=y and no tmem backend registers > Case C) CONFIG_FRONTSWAP=y and a tmem backend DOES register ... > The point is that only Case C has possible interactions > so Case A and Case B end-users and kernel developers need > not worry about the maintenance. I'm personally evaluating this as if all the distributions would turn it on. I'm evaluating as if every one of my employer's systems ships with it and as if it is =y my laptop. Basically, I'm evaluating A/B/C and only looking at the worst-case maintenance cost (C). In other words, I'm ignoring A/B and assuming wide use. I'm curious where you expect to see the code get turned on and used since we might be looking at this from different angles. -- Dave