From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with ESMTP id 209A28D0080 for ; Wed, 17 Nov 2010 03:16:55 -0500 (EST) Received: from wpaz17.hot.corp.google.com (wpaz17.hot.corp.google.com [172.24.198.81]) by smtp-out.google.com with ESMTP id oAH8Gqg8003631 for ; Wed, 17 Nov 2010 00:16:53 -0800 Received: from iwn38 (iwn38.prod.google.com [10.241.68.102]) by wpaz17.hot.corp.google.com with ESMTP id oAH8Gpsv030436 for ; Wed, 17 Nov 2010 00:16:51 -0800 Received: by iwn38 with SMTP id 38so566861iwn.6 for ; Wed, 17 Nov 2010 00:16:50 -0800 (PST) Date: Wed, 17 Nov 2010 00:16:47 -0800 (PST) From: David Rientjes Subject: Re: [2/8,v3] NUMA Hotplug Emulator: infrastructure of NUMA hotplug emulation In-Reply-To: <20101117021000.568681101@intel.com> Message-ID: References: <20101117020759.016741414@intel.com> <20101117021000.568681101@intel.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: Shaohui Zheng Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, haicheng.li@linux.intel.com, lethal@linux-sh.org, ak@linux.intel.com, shaohui.zheng@linux.intel.com, Yinghai Lu , Haicheng Li List-ID: On Wed, 17 Nov 2010, shaohui.zheng@intel.com wrote: > From: Haicheng Li > > NUMA hotplug emulator introduces a new node state N_HIDDEN to > identify the fake offlined node. It firstly hides RAM via E820 > table and then emulates fake offlined nodes with the hidden RAM. > Hmm, why can't you use numa=hide to hide a specified quantity of memory from the kernel and then use the add_memory() interface to hot-add the offlined memory in the desired quantity? In other words, why do you need to track the offlined nodes with a state? The userspace interface would take a desired size of hidden memory to hot-add and the node id would be the first_unset_node(node_online_map). > After system bootup, user is able to hotplug-add these offlined > nodes, which is just similar to a real hardware hotplug behavior. > > Using boot option "numa=hide=N*size" to fake offlined nodes: > - N is the number of hidden nodes > - size is the memory size (in MB) per hidden node. > size should be parsed with memparse() so users can specify 'M' or 'G', it would even make your parsing code simpler. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org