From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 27 Feb 2008 14:04:15 +0900 From: KOSAKI Motohiro Subject: Re: [RFC][PATCH] page reclaim throttle take2 In-Reply-To: <20080227140042.66abb805.kamezawa.hiroyu@jp.fujitsu.com> References: <20080227133850.4249.KOSAKI.MOTOHIRO@jp.fujitsu.com> <20080227140042.66abb805.kamezawa.hiroyu@jp.fujitsu.com> Message-Id: <20080227140221.424C.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: KAMEZAWA Hiroyuki Cc: kosaki.motohiro@jp.fujitsu.com, balbir@linux.vnet.ibm.com, Peter Zijlstra , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Rik van Riel , Lee Schermerhorn , Nick Piggin List-ID: Hi > > 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? > > > How about adding something like.. > == > CONFIG_SIMULTANEOUS_PAGE_RECLAIMERS > int > default 3 > depends on DEBUG > help > This value determines the number of threads which can do page reclaim > in a zone simultaneously. If this is too big, performance under heavy memory > pressure will decrease. > If unsure, use default. > == > > Then, you can get performance reports from people interested in this > feature in test cycle. hm, intersting. but sysctl parameter is more better, i think. OK, I'll add it at next post. -- 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