From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 27 Feb 2008 13:45:18 +0900 From: KOSAKI Motohiro Subject: Re: [RFC][PATCH] page reclaim throttle take2 In-Reply-To: <47C4E6CD.6090401@linux.vnet.ibm.com> References: <20080227131939.4244.KOSAKI.MOTOHIRO@jp.fujitsu.com> <47C4E6CD.6090401@linux.vnet.ibm.com> Message-Id: <20080227133850.4249.KOSAKI.MOTOHIRO@jp.fujitsu.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: balbir@linux.vnet.ibm.com Cc: kosaki.motohiro@jp.fujitsu.com, Peter Zijlstra , linux-kernel@vger.kernel.org, linux-mm@kvack.org, KAMEZAWA Hiroyuki , Rik van Riel , Lee Schermerhorn , Nick Piggin List-ID: Hi > One more thing, I would request you to add default heuristics (number of > reclaimers), based on the number of cpus in the system. Letting people tuning it > is fine, but defaults should be related to number of cpus, nodes and zones on > the system. Zones can be reaped in parallel per node and cpus allow threads to > run in parallel. So please use that to come up with good defaults, instead of a > number like "3". I don't think so. all modern many cpu machine stand on NUMA. it mean following, - if cpu increases, then zone increases, too. if default value increase by #cpus, lock contension dramatically increase on large numa. Have I overlooked anything? and, (but) i afraid to 3 is too small value. if you have another test result on large machine, please show me. - kosaki -- 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