Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754924Ab2BPTIQ (ORCPT ); Thu, 16 Feb 2012 14:08:16 -0500 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:52916 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752014Ab2BPTIN (ORCPT ); Thu, 16 Feb 2012 14:08:13 -0500 Message-ID: <4F3D53F9.8040508@fb.com> Date: Thu, 16 Feb 2012 11:07:37 -0800 From: Arun Sharma User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:9.0) Gecko/20111222 Thunderbird/9.0.1 MIME-Version: 1.0 To: Andrea Righi CC: Andrew Morton , Minchan Kim , Peter Zijlstra , Johannes Weiner , KAMEZAWA Hiroyuki , KOSAKI Motohiro , Rik van Riel , Hugh Dickins , Alexander Viro , Shaohua Li , =?ISO-8859-1?Q?P=E1draig_Brady?= , John Stultz , Jerry James , Julius Plenz , linux-mm , , LKML Subject: Re: [PATCH v5 3/3] fadvise: implement POSIX_FADV_NOREUSE References: <1329006098-5454-1-git-send-email-andrea@betterlinux.com> <1329006098-5454-4-git-send-email-andrea@betterlinux.com> <20120215233537.GA20724@dev3310.snc6.facebook.com> <20120215234724.GA21685@thinkpad> <4F3C467B.1@fb.com> <20120216005608.GC21685@thinkpad> <4F3C6594.3030709@fb.com> <20120216103944.GA1440@thinkpad> <4F3D4E34.9060105@fb.com> <20120216185753.GD13354@thinkpad> In-Reply-To: <20120216185753.GD13354@thinkpad> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [192.168.18.252] X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.6.7361,1.0.260,0.0.0000 definitions=2012-02-16_06:2012-02-16,2012-02-16,1970-01-01 signatures=0 X-Proofpoint-Spam-Reason: safe Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1197 Lines: 29 On 2/16/12 10:57 AM, Andrea Righi wrote: > Maybe we should try to push ...something... in the memcg code for the > short-term future, make it as much generic as possible, and for the > long-term try to reuse the same feature (totally or in part) in the > per-fd approach via fadvise(). Yes - the two approaches are complementary and we should probably pursue both. There are a number of apps which are already using fadvise though: https://issues.apache.org/jira/browse/MAPREDUCE-3289 http://highscalability.com/blog/2012/1/12/peregrine-a-map-reduce-framework-for-iterative-and-pipelined.html and probably many other similar cases that are not open source. Some of these apps may be better off using NOREUSE instead of DONTNEED, since they may not have a clue on what else is going on in the system. The way I think about it: NOREUSE is a statement about what my process is doing and DONTNEED is a statement about the entire system. -Arun -- 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/