From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751812AbZECBrs (ORCPT ); Sat, 2 May 2009 21:47:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750904AbZECBrj (ORCPT ); Sat, 2 May 2009 21:47:39 -0400 Received: from mga14.intel.com ([143.182.124.37]:40685 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750892AbZECBrj (ORCPT ); Sat, 2 May 2009 21:47:39 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.40,284,1239001200"; d="scan'208";a="138543997" Date: Sun, 3 May 2009 09:46:55 +0800 From: Wu Fengguang To: Rik van Riel Cc: KOSAKI Motohiro , Peter Zijlstra , Elladan , "linux-kernel@vger.kernel.org" , "tytso@mit.edu" , "linux-mm@kvack.org" Subject: Re: [PATCH] vmscan: evict use-once pages first (v3) Message-ID: <20090503014655.GA6794@localhost> References: <20090428044426.GA5035@eskimo.com> <20090428192907.556f3a34@bree.surriel.com> <1240987349.4512.18.camel@laptop> <20090429114708.66114c03@cuia.bos.redhat.com> <2f11576a0904290907g48e94e74ye97aae593f6ac519@mail.gmail.com> <20090429131436.640f09ab@cuia.bos.redhat.com> <20090503011540.GA5702@localhost> <20090502213356.2f620d81@riellaptop.surriel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090502213356.2f620d81@riellaptop.surriel.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, May 03, 2009 at 09:33:56AM +0800, Rik van Riel wrote: > On Sun, 3 May 2009 09:15:40 +0800 > Wu Fengguang wrote: > > > In the worse scenario, it could waste half the memory that could > > otherwise be used for readahead buffer and to prevent thrashing, in a > > server serving large datasets that are hardly reused, but still slowly > > builds up its active list during the long uptime (think about a slowly > > performance downgrade that can be fixed by a crude dropcache action). > > In the best case, the active list ends up containing all the > indirect blocks for the files that are occasionally reused, > and the system ends up being able to serve its clients with > less disk IO. > > For systems like ftp.kernel.org, the files that are most > popular will end up on the active list, without being kicked > out by the files that are less popular. Sure, such good cases tend to be prevalent - so obvious that I didn't mind to mention ;-) From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail137.messagelabs.com (mail137.messagelabs.com [216.82.249.19]) by kanga.kvack.org (Postfix) with SMTP id 657A86B003D for ; Sat, 2 May 2009 21:46:56 -0400 (EDT) Date: Sun, 3 May 2009 09:46:55 +0800 From: Wu Fengguang Subject: Re: [PATCH] vmscan: evict use-once pages first (v3) Message-ID: <20090503014655.GA6794@localhost> References: <20090428044426.GA5035@eskimo.com> <20090428192907.556f3a34@bree.surriel.com> <1240987349.4512.18.camel@laptop> <20090429114708.66114c03@cuia.bos.redhat.com> <2f11576a0904290907g48e94e74ye97aae593f6ac519@mail.gmail.com> <20090429131436.640f09ab@cuia.bos.redhat.com> <20090503011540.GA5702@localhost> <20090502213356.2f620d81@riellaptop.surriel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090502213356.2f620d81@riellaptop.surriel.com> Sender: owner-linux-mm@kvack.org To: Rik van Riel Cc: KOSAKI Motohiro , Peter Zijlstra , Elladan , "linux-kernel@vger.kernel.org" , "tytso@mit.edu" , "linux-mm@kvack.org" List-ID: On Sun, May 03, 2009 at 09:33:56AM +0800, Rik van Riel wrote: > On Sun, 3 May 2009 09:15:40 +0800 > Wu Fengguang wrote: > > > In the worse scenario, it could waste half the memory that could > > otherwise be used for readahead buffer and to prevent thrashing, in a > > server serving large datasets that are hardly reused, but still slowly > > builds up its active list during the long uptime (think about a slowly > > performance downgrade that can be fixed by a crude dropcache action). > > In the best case, the active list ends up containing all the > indirect blocks for the files that are occasionally reused, > and the system ends up being able to serve its clients with > less disk IO. > > For systems like ftp.kernel.org, the files that are most > popular will end up on the active list, without being kicked > out by the files that are less popular. Sure, such good cases tend to be prevalent - so obvious that I didn't mind to mention ;-) -- 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