Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759377AbZGIBU6 (ORCPT ); Wed, 8 Jul 2009 21:20:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757162AbZGIBUu (ORCPT ); Wed, 8 Jul 2009 21:20:50 -0400 Received: from mx2.redhat.com ([66.187.237.31]:53802 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756457AbZGIBUt (ORCPT ); Wed, 8 Jul 2009 21:20:49 -0400 Message-ID: <4A5545CC.9030909@redhat.com> Date: Wed, 08 Jul 2009 21:20:12 -0400 From: Rik van Riel Organization: Red Hat, Inc User-Agent: Thunderbird 2.0.0.17 (X11/20080915) MIME-Version: 1.0 To: Anthony Liguori CC: Dan Magenheimer , linux-kernel@vger.kernel.org, npiggin@suse.de, akpm@osdl.org, jeremy@goop.org, xen-devel@lists.xensource.com, tmem-devel@oss.oracle.com, alan@lxorguk.ukuu.org.uk, linux-mm@kvack.org, kurt.hackel@oracle.com, Rusty Russell , dave.mccracken@oracle.com, Marcelo Tosatti , sunil.mushran@oracle.com, Avi Kivity , Schwidefsky , chris.mason@oracle.com, Balbir Singh Subject: Re: [RFC PATCH 0/4] (Take 2): transcendent memory ("tmem") for Linux References: <482d25af-01eb-4c2a-9b1d-bdaf4020ce88@default> <4A55243B.8090001@codemonkey.ws> In-Reply-To: <4A55243B.8090001@codemonkey.ws> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1103 Lines: 32 Anthony Liguori wrote: > I have trouble mapping this to a VMM capable of overcommit without just > coming back to CMM2. Same for me. CMM2 has a more complex mechanism, but way easier policy than anything else out there. > In CMM2 parlance, ephemeral tmem pools is just normal kernel memory > marked in the volatile state, no? Basically. > It seems to me that an architecture built around hinting would be more > robust than having to use separate memory pools for this type of memory > (especially since you are requiring a copy to/from the pool). I agree. Something along the lines of CMM2 needs more infrastructure, but will be infinitely easier to get right from the policy side. Automatic ballooning is an option too, with fairly simple infrastructure, but potentially insanely complex policy issues to sort out... -- All rights reversed. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/