From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 7 Aug 2007 17:55:47 +0100 Subject: Re: [PATCH] Apply memory policies to top two highest zones when highest zone is ZONE_MOVABLE Message-ID: <20070807165546.GA7603@skynet.ie> References: <20070802172118.GD23133@skynet.ie> <200708040002.18167.ak@suse.de> <20070806121558.e1977ba5.akpm@linux-foundation.org> <200708062231.49247.ak@suse.de> <20070806215541.GC6142@skynet.ie> <20070806221252.aa1e9048.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20070806221252.aa1e9048.akpm@linux-foundation.org> From: mel@skynet.ie (Mel Gorman) Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: Andi Kleen , Lee.Schermerhorn@hp.com, clameter@sgi.com, kamezawa.hiroyu@jp.fujitsu.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: On (06/08/07 22:12), Andrew Morton didst pronounce: > On Mon, 6 Aug 2007 22:55:41 +0100 mel@skynet.ie (Mel Gorman) wrote: > > > On (06/08/07 22:31), Andi Kleen didst pronounce: > > > > > > > If correct, I would suggest merging the horrible hack for .23 then taking > > > > it out when we merge "grouping pages by mobility". But what if we don't do > > > > that merge? > > > > > > Or disable ZONE_MOVABLE until it is usable? > > > > It's usable now. The issue with policies only occurs if the user specifies > > kernelcore= or movablecore= on the command-line. Your language suggests > > that you believe policies are not applied when ZONE_MOVABLE is configured > > at build-time. > > So.. the problem which we're fixing here is only present when someone > use kernelcore=. This is in fact an argument for _not_ merging the > horrible-hack. > It's even more constrained than that. It only applies to the MPOL_BIND policy when kernelcore= is specified. The other policies work the same as they ever did. > How commonly do we expect people to specify kernelcore=? If "not much" then > it isn't worth adding the __alloc_pages() overhead? > For 2.6.23 at least, it'll be "not much". While I'm not keen on leaving MPOL_BIND as it is for 2.6.23, we can postpone the final decision until we've bashed the one-zonelist-per-node patches a bit and see do we want to do that instead. > (It's a pretty darn small overhead, I must say) And it's simplier than the one-zone-list-per-node patches. The current draft of the patch I'm working on looks something like; arch/parisc/mm/init.c | 10 ++- drivers/char/sysrq.c | 2 fs/buffer.c | 2 include/linux/gfp.h | 3 - include/linux/mempolicy.h | 2 include/linux/mmzone.h | 42 +++++++++++++++ include/linux/swap.h | 2 mm/mempolicy.c | 6 +- mm/mmzone.c | 28 ++++++++++ mm/oom_kill.c | 8 +-- mm/page_alloc.c | 122 +++++++++++++++++++++------------------------- mm/slab.c | 11 ++-- mm/slub.c | 11 ++-- mm/vmscan.c | 16 +++--- 14 files changed, 164 insertions(+), 101 deletions(-) -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- 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