From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 26 Apr 2007 23:32:07 -0700 From: Andrew Morton Subject: Re: [patch 09/10] SLUB: Exploit page mobility to increase allocation order Message-Id: <20070426233207.a86faf0a.akpm@linux-foundation.org> In-Reply-To: <20070427042909.415420974@sgi.com> References: <20070427042655.019305162@sgi.com> <20070427042909.415420974@sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: clameter@sgi.com Cc: linux-mm@kvack.org, Mel Gorman List-ID: On Thu, 26 Apr 2007 21:27:04 -0700 clameter@sgi.com wrote: > If there is page mobility then we can defragment memory. So its possible to > use higher order of pages for slab allocations. > > If the defaults were not overridden set the max order to 4 and guarantee 16 > objects per slab. This will put some stress on Mel's antifrag approaches. > If these defaults are too large then they should be later reduced. > > Cc: Mel Gorman > Signed-off-by: Christoph Lameter > > Index: linux-2.6.21-rc7-mm2/include/linux/mmzone.h > =================================================================== > --- linux-2.6.21-rc7-mm2.orig/include/linux/mmzone.h 2007-04-26 20:57:58.000000000 -0700 > +++ linux-2.6.21-rc7-mm2/include/linux/mmzone.h 2007-04-26 21:05:48.000000000 -0700 > @@ -25,6 +25,8 @@ > #endif > #define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1)) > > +extern int page_group_by_mobility_disabled; > + This creates unfortunate linkage between your stuff and Mel's stuff. And afaik nobody has done a detailed review of Mel's stuff in a year or three. I will do so, but you know how it is. (that kernelcore= thing smells like highmem to me). I'm a bit wobbly about merging it all at this stage. So I'll queue this patch up somewhere from where it can be easily dropped again, but it makes further patches a bit trickier. Please keep them as fine-grained as poss. -- 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