Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932127Ab0LMCIs (ORCPT ); Sun, 12 Dec 2010 21:08:48 -0500 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:41791 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756189Ab0LMCIr (ORCPT ); Sun, 12 Dec 2010 21:08:47 -0500 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 Date: Mon, 13 Dec 2010 11:03:01 +0900 From: KAMEZAWA Hiroyuki To: Mel Gorman Cc: Andrew Morton , Simon Kirby , KOSAKI Motohiro , Shaohua Li , Dave Hansen , Johannes Weiner , linux-mm , linux-kernel Subject: Re: [PATCH 2/6] mm: kswapd: Keep kswapd awake for high-order allocations until a percentage of the node is balanced Message-Id: <20101213110301.655194ed.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <1291995985-5913-3-git-send-email-mel@csn.ul.ie> References: <1291995985-5913-1-git-send-email-mel@csn.ul.ie> <1291995985-5913-3-git-send-email-mel@csn.ul.ie> Organization: FUJITSU Co. LTD. X-Mailer: Sylpheed 3.0.3 (GTK+ 2.10.14; i686-pc-mingw32) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1194 Lines: 24 On Fri, 10 Dec 2010 15:46:21 +0000 Mel Gorman wrote: > When reclaiming for high-orders, kswapd is responsible for balancing a > node but it should not reclaim excessively. It avoids excessive reclaim by > considering if any zone in a node is balanced then the node is balanced. In > the cases where there are imbalanced zone sizes (e.g. ZONE_DMA with both > ZONE_DMA32 and ZONE_NORMAL), kswapd can go to sleep prematurely as just > one small zone was balanced. > > This alters the sleep logic of kswapd slightly. It counts the number of pages > that make up the balanced zones. If the total number of balanced pages is > more than a quarter of the zone, kswapd will go back to sleep. This should > keep a node balanced without reclaiming an excessive number of pages. > > Signed-off-by: Mel Gorman > Reviewed-by: Minchan Kim Reviewed-by: KAMEZAWA Hiroyuki -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/