From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <469751E9.7060904@shadowen.org> Date: Fri, 13 Jul 2007 11:20:25 +0100 From: Andy Whitcroft MIME-Version: 1.0 Subject: Re: -mm merge plans -- anti-fragmentation References: <20070710102043.GA20303@skynet.ie> <20070712122925.192a6601.akpm@linux-foundation.org> In-Reply-To: <20070712122925.192a6601.akpm@linux-foundation.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: Mel Gorman , npiggin@suse.de, kenchen@google.com, jschopp@austin.ibm.com, kamezawa.hiroyu@jp.fujitsu.com, a.p.zijlstra@chello.nl, y-goto@jp.fujitsu.com, clameter@sgi.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: Andrew Morton wrote: > On Tue, 10 Jul 2007 11:20:43 +0100 > mel@skynet.ie (Mel Gorman) wrote: > >>> create-the-zone_movable-zone.patch >>> allow-huge-page-allocations-to-use-gfp_high_movable.patch >>> handle-kernelcore=-generic.patch >>> >>> Mel's moveable-zone work. In a similar situation. We need to stop whatever >>> we're doing and get down and work out what we're going to do with all this >>> stuff. >>> >> Whatever about grouping pages by mobility, I would like to see these go >> through. They have a real application for hugetlb pool resizing where the >> administrator knows the range of hugepages that will be required but doesn't >> want to waste memory when the required number of hugepages is small. I've >> cc'd Kenneth Chen as I believe he has run into this problem recently where >> I believe partitioning memory would have helped. He'll either confirm or deny. > > Still no decision here, really. > > Should we at least go for > > add-__gfp_movable-for-callers-to-flag-allocations-from-high-memory-that-may-be-migrated.patch > create-the-zone_movable-zone.patch > allow-huge-page-allocations-to-use-gfp_high_movable.patch > handle-kernelcore=-generic.patch > > in 2.6.23? These patches are pretty simple and self-contained utilising the existing zone infrastructure. They provide a significant degree of placement control when configured, which gives a lot of the benefits of grouping-pages-by-mobility. Merging these would seem like a low-risk option. Having a degree of placement control as delivered by ZONE_MOVABLE greatly increases the effectiveness of lumpy reclaim at higher orders. These patches plus lumpy would (IMO) provide a good base for further development. In particular I would envisage better usability for hugepage users in terms of simpler configuration. I would like to see ZONE_MOVABLE and lumpy considered for 2.6.23. -apw -- 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