Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751821Ab0GYJsO (ORCPT ); Sun, 25 Jul 2010 05:48:14 -0400 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:43305 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750910Ab0GYJsJ convert rfc822-to-8bit (ORCPT ); Sun, 25 Jul 2010 05:48:09 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 From: KOSAKI Motohiro To: Balbir Singh Subject: Re: [PATCH 1/7] memcg: sc.nr_to_reclaim should be initialized Cc: kosaki.motohiro@jp.fujitsu.com, LKML , linux-mm , Andrew Morton , Mel Gorman , KAMEZAWA Hiroyuki , Nishimura Daisuke In-Reply-To: References: <20100723154638.88C8.A69D9226@jp.fujitsu.com> Message-Id: <20100725184322.40CF.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 8BIT X-Mailer: Becky! ver. 2.50.07 [ja] Date: Sun, 25 Jul 2010 18:48:06 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1194 Lines: 32 > >> 1. How far does this push pages (in terms of when limit is hit)? > > > > 32 pages per mem_cgroup_shrink_node_zone(). > > > > That said, the algorithm is here. > > > > 1. call mem_cgroup_largest_soft_limit_node() > > ? calculate largest cgroup > > 2. call mem_cgroup_shrink_node_zone() and shrink 32 pages > > 3. goto 1 if limit is still exceed. > > > > If it's not your intention, can you please your intended algorithm? > > We set it to 0, since we care only about a single page reclaim on > hitting the limit. IIRC, in the past we saw an excessive pushback on > reclaiming SWAP_CLUSTER_MAX pages, just wanted to check if you are > seeing the same behaviour even now after your changes. Actually, we have 32 pages reclaim batch size. (see nr_scan_try_batch() and related functions) thus <32 value doesn't works as your intended. But, If you run your test again, and (if there is) report any bugs. I'm very glad and fix it soon. Thanks. -- 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/