From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <43679EE6.7000706@jp.fujitsu.com> Date: Wed, 02 Nov 2005 01:59:18 +0900 From: Kamezawa Hiroyuki MIME-Version: 1.0 Subject: Re: [Lhms-devel] [PATCH 0/7] Fragmentation Avoidance V19 References: <4366A8D1.7020507@yahoo.com.au> <4366C559.5090504@yahoo.com.au> <4366D469.2010202@yahoo.com.au> <20051101135651.GA8502@elte.hu> <1130854224.14475.60.camel@localhost> <20051101142959.GA9272@elte.hu> <1130856555.14475.77.camel@localhost> <20051101150142.GA10636@elte.hu> <43679C69.6050107@jp.fujitsu.com> In-Reply-To: <43679C69.6050107@jp.fujitsu.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Kamezawa Hiroyuki Cc: Ingo Molnar , Dave Hansen , Mel Gorman , Nick Piggin , "Martin J. Bligh" , Andrew Morton , kravetz@us.ibm.com, linux-mm , Linux Kernel Mailing List , lhms List-ID: Kamezawa Hiroyuki wrote: > Ingo Molnar wrote: > >> so it's all about expectations: _could_ you reasonably remove a piece >> of RAM? Customer will say: "I have stopped all nonessential services, >> and free RAM is at 90%, still I cannot remove that piece of faulty >> RAM, fix the kernel!". No reasonable customer will say: "True, I have >> all RAM used up in mlock()ed sections, but i want to remove some RAM >> nevertheless". >> > Hi, I'm one of men in -lhms > > In my understanding... > - Memory Hotremove on IBM's LPAR? approach is > [remove some amount of memory from somewhere.] > For this approach, Mel's patch will work well. > But this will not guaranntee a user can remove specified range of > memory at any time because how memory range is used is not defined by > an admin > but by the kernel automatically. But to extract some amount of memory, > Mel's patch is very important and they need this. > One more consideration... Some cpus which support virtialization will be shipped by some vendor in near future. If someone uses vitualized OS, only problem is *resizing*. Hypervisor will be able to remap semi-physical pages anyware with hardware assistance but system resizing needs operating system assistance. To this direction, [remove some amount of memory from somewhere.] is important approach. -- Kame -- 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/ . Don't email: email@kvack.org