From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753652Ab3ACQ2U (ORCPT ); Thu, 3 Jan 2013 11:28:20 -0500 Received: from e34.co.us.ibm.com ([32.97.110.152]:40919 "EHLO e34.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753580Ab3ACQ2Q (ORCPT ); Thu, 3 Jan 2013 11:28:16 -0500 Message-ID: <50E5B173.7070807@linux.vnet.ibm.com> Date: Thu, 03 Jan 2013 08:27:31 -0800 From: Dave Hansen User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: Minchan Kim CC: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Rik van Riel , Hugh Dickins , Andrea Arcangeli Subject: Re: [RFC 2/8] Don't allow volatile attribute on THP and KSM References: <1357187286-18759-1-git-send-email-minchan@kernel.org> <1357187286-18759-3-git-send-email-minchan@kernel.org> In-Reply-To: <1357187286-18759-3-git-send-email-minchan@kernel.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13010316-2876-0000-0000-000003C6F754 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/02/2013 08:28 PM, Minchan Kim wrote: > VOLATILE imply the the pages in the range isn't working set any more > so it's pointless that make them to THP/KSM. One of the points of this implementation is that it be able to preserve memory contents when there is no pressure. If those contents happen to contain a THP/KSM page, and there's no pressure, it seems like the right thing to do is to leave that memory in place. It might be a fair thing to do this in order to keep the implementation more sane at the moment. But, we should make sure there's some good text on that in the changelog.