From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758908Ab2KWC0J (ORCPT ); Thu, 22 Nov 2012 21:26:09 -0500 Received: from mga01.intel.com ([192.55.52.88]:18728 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756873Ab2KWC0I (ORCPT ); Thu, 22 Nov 2012 21:26:08 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.83,304,1352102400"; d="scan'208";a="251261115" Date: Fri, 23 Nov 2012 10:25:57 +0800 From: Fengguang Wu To: Jaegeuk Hanse Cc: metin d , Jan Kara , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" Subject: Re: Problem in Page Cache Replacement Message-ID: <20121123022557.GA3954@localhost> References: <1353433362.85184.YahooMailNeo@web141101.mail.bf1.yahoo.com> <20121120182500.GH1408@quack.suse.cz> <1353485020.53500.YahooMailNeo@web141104.mail.bf1.yahoo.com> <1353485630.17455.YahooMailNeo@web141106.mail.bf1.yahoo.com> <50AC9220.70202@gmail.com> <20121121090204.GA9064@localhost> <50ACA209.9000101@gmail.com> <20121122152611.GA11736@localhost> <50AED214.4000701@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <50AED214.4000701@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Jaegeuk, > Thanks for your response. But which kind of pages are in the special > reserved and which are all-flags-cleared? The all-flags-cleared pages are mostly free pages in the buddy system. The pages with flag "buddy" are also free pages: the buddy system only marks the head pages of each order-2 free range with flag "buddy". The reserved pages come from many sources, they may be set for memory reserved for BIOS, memory holes, offlined memory, or used by some device drivers. Thanks, Fengguang