Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261404AbVBRRMC (ORCPT ); Fri, 18 Feb 2005 12:12:02 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261420AbVBRRLe (ORCPT ); Fri, 18 Feb 2005 12:11:34 -0500 Received: from omx2-ext.sgi.com ([192.48.171.19]:58024 "EHLO omx2.sgi.com") by vger.kernel.org with ESMTP id S261404AbVBRRJ6 (ORCPT ); Fri, 18 Feb 2005 12:09:58 -0500 Message-ID: <42161FBF.70200@sgi.com> Date: Fri, 18 Feb 2005 11:02:55 -0600 From: Ray Bryant User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.2) Gecko/20040805 Netscape/7.2 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Andi Kleen CC: Andi Kleen , Ray Bryant , linux-mm , linux-kernel Subject: Re: [RFC 2.6.11-rc2-mm2 0/7] mm: manual page migration -- overview II References: <20050212032535.18524.12046.26397@tomahawk.engr.sgi.com> <42114279.5070202@sgi.com> <20050215121404.GB25815@muc.de> <421241A2.8040407@sgi.com> <20050215214831.GC7345@wotan.suse.de> <4212C1A9.1050903@sgi.com> <20050217235437.GA31591@wotan.suse.de> In-Reply-To: <20050217235437.GA31591@wotan.suse.de> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1392 Lines: 38 Andi Kleen wrote: > You and Robin mentioned some problems with "double migration" > with that, but it's still not completely clear to me what > problem you're solving here. Perhaps that needs to be reexamined. > > There is one other case where Robin and I have talked about double migration. That is the case where the set of old nodes and new nodes overlap. If one is not careful, and the system call interface is assumed to be something like: page_migrate(pid, old_node, new_node); then if one is not careful (and depending on what the complete list of old_nodes and new_nodes are), then if one does something like: page_migrate(pid, 1, 2); page_migrate(pid, 2, 3); then you can end up actually moving pages from node 1 to node 2, only to move them again from node 2 to node 3. This is another form of double migration that we have worried about avoiding. -- ----------------------------------------------- Ray Bryant 512-453-9679 (work) 512-507-7807 (cell) raybry@sgi.com raybry@austin.rr.com The box said: "Requires Windows 98 or better", so I installed Linux. ----------------------------------------------- - 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/