From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from westrelay02.boulder.ibm.com (westrelay02.boulder.ibm.com [9.17.195.11]) by e35.co.us.ibm.com (8.12.11/8.12.11) with ESMTP id jA2AsnqA024941 for ; Wed, 2 Nov 2005 05:54:49 -0500 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by westrelay02.boulder.ibm.com (8.12.10/NCO/VERS6.7) with ESMTP id jA2AsnXg516968 for ; Wed, 2 Nov 2005 03:54:49 -0700 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.12.11/8.13.3) with ESMTP id jA2AsmuI006087 for ; Wed, 2 Nov 2005 03:54:49 -0700 Subject: Re: [Lhms-devel] [PATCH 0/7] Fragmentation Avoidance V19 From: Dave Hansen In-Reply-To: <43688B74.20002@yahoo.com.au> 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> <436880B8.1050207@yahoo.com.au> <1130923969.15627.11.camel@localhost> <43688B74.20002@yahoo.com.au> Content-Type: text/plain Date: Wed, 02 Nov 2005 11:54:35 +0100 Message-Id: <1130928875.15627.24.camel@localhost> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Nick Piggin Cc: Ingo Molnar , 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: On Wed, 2005-11-02 at 20:48 +1100, Nick Piggin wrote: > > So, if you have to add to NORMAL/DMA on the fly, how do you handle a > > case where the new NORMAL/DMA ram is physically above > > HIGHMEM/HOTPLUGGABLE? Is there any other course than to make a zone > > required to be able to span other zones, and be noncontiguous? Would > > that represent too much of a change to the current model? > > > > Perhaps. Perhaps it wouldn't be required to get a solution that is > "good enough" though. > > But if you can reclaim your ZONE_RECLAIMABLE, then you could reclaim > it all and expand your normal zones into it, bottom up. That's a good point. It would be slow, because you have to wait on page reclaim, but it would work. I do worry a bit that this might make adding memory to slow of an operation to be useful for short periods, but we'll see how it actually behaves. -- Dave -- 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