From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [PATCH] 2.6.23-rc1-mm1 - fix missing numa_zonelist_order sysctl From: Lee Schermerhorn In-Reply-To: <20070802094445.6495e25d.kamezawa.hiroyu@jp.fujitsu.com> References: <1185994972.5059.91.camel@localhost> <20070802094445.6495e25d.kamezawa.hiroyu@jp.fujitsu.com> Content-Type: text/plain Date: Thu, 02 Aug 2007 11:07:38 -0400 Message-Id: <1186067258.5040.33.camel@localhost> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: KAMEZAWA Hiroyuki Cc: Andrew Morton , linux-kernel , linux-mm , Christoph Lameter List-ID: On Thu, 2007-08-02 at 09:44 +0900, KAMEZAWA Hiroyuki wrote: > On Wed, 01 Aug 2007 15:02:51 -0400 > Lee Schermerhorn wrote: > > [But, maybe reordering the zonelists is not such a good idea > > when ZONE_MOVABLE is populated?] > > > > It's case-by-case I think. In zone order with ZONE_MOVABLE case, > user's page cache will not use ZONE_NORMAL until ZONE_MOVABLE in all node > is exhausted. This is an expected behavior, I think. > > I think the real problem is the scheme for "How to set zone movable size to > appropriate value for the system". This needs more study and documentation. > (but maybe depends on system configuration to some extent.) Yes. Having thought about it a bit more, maybe zone order IS what we want if we desire the remainder of the zone from which is was taken [ZONE_MOVABLE-1] to be reserved for non-movable kernel use as long as possible--similar to the dma zone. I had made the non-movable zone very large for testing, so that I could create a segment that used all of the movable zones on all the nodes and then dip into the non-movable/normal zone. If I used a more reasonable [much smaller] amount of kernelcore, the interleave would have worked as "expected". Of course, I don't have any idea of what is a "reasonable amount". Guess I could look at non-movable zone memory usage in a system at typical or peak load to get an idea. Anyone have any data in this regard? Lee -- 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