From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <436880B8.1050207@yahoo.com.au> Date: Wed, 02 Nov 2005 20:02:48 +1100 From: Nick Piggin MIME-Version: 1.0 Subject: Re: [Lhms-devel] [PATCH 0/7] Fragmentation Avoidance V19 References: <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> <1130858580.14475.98.camel@localhost> <20051102084946.GA3930@elte.hu> In-Reply-To: <20051102084946.GA3930@elte.hu> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Ingo Molnar Cc: Dave Hansen , Mel Gorman , "Martin J. Bligh" , Andrew Morton , Linus Torvalds , kravetz@us.ibm.com, linux-mm , Linux Kernel Mailing List , lhms , Arjan van de Ven List-ID: Ingo Molnar wrote: > really, once you accept that, the path out of this mess becomes 'easy': > we _have to_ compromise on the feature side! And the moment we give up > the notion of 'generic kernel RAM' and focus on the hot-removability of > a limited-functionality zone, the complexity of the solution becomes > three orders of magnitude smaller. No fragmentation avoidance necessary. > No 'have to handle dozens of very hard problems to become 99% > functional' issues. Once you make that zone an opt-in thing, it becomes > much better from a development dynamics point of view as well. > I agree. Especially considering that all this memory hotplug usage for hypervisors etc. is a relatively new thing with few of our userbase actually using it. I think a simple zones solution is the right way to go for now. In future, if we have a large proportion of users who want it, and their requirements are better understood, and there is still no hardware / hypervisor support for handling this for us, *then* it is time to re-evaluate our compromise. -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com -- 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