From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756817Ab2BPCLP (ORCPT ); Wed, 15 Feb 2012 21:11:15 -0500 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:52046 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754791Ab2BPCLM (ORCPT ); Wed, 15 Feb 2012 21:11:12 -0500 Message-ID: <4F3C6594.3030709@fb.com> Date: Wed, 15 Feb 2012 18:10:28 -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 , =?UTF-8?B?UMOhZHJhaWcgQnJhZHk=?= , 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> In-Reply-To: <20120216005608.GC21685@thinkpad> Content-Type: text/plain; charset="UTF-8"; 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_01:2012-02-16,2012-02-16,1970-01-01 signatures=0 X-Proofpoint-Spam-Reason: safe Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/15/12 4:56 PM, Andrea Righi wrote: > Oh sorry, you're right! nocache_tree is not a pointer inside > address_space, so the compiler must know the size. > > mmh... move the definition of the rb_root struct in linux/types.h? or > simply use a rb_root pointer. The (void *) looks a bit scary and too bug > prone. Either way is fine. I did some black box testing of the patch (comparing noreuse vs dontneed) and it behaves as expected. On a file copy, neither one pollutes the page cache. But if I run a random read benchmark on the source file right before and afterwards, page cache is warm with noreuse, but cold with dontneed. Copy performance was unaffected. I can't really comment on the implementation details since I haven't reviewed it, but the functionality sounds useful. -Arun From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arun Sharma Subject: Re: [PATCH v5 3/3] fadvise: implement POSIX_FADV_NOREUSE Date: Wed, 15 Feb 2012 18:10:28 -0800 Message-ID: <4F3C6594.3030709@fb.com> 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> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit Cc: Andrew Morton , Minchan Kim , Peter Zijlstra , Johannes Weiner , KAMEZAWA Hiroyuki , KOSAKI Motohiro , Rik van Riel , Hugh Dickins , Alexander Viro , Shaohua Li , =?UTF-8?B?UMOhZHJhaWcgQnJhZHk=?= , John Stultz , Jerry James , Julius Plenz , linux-mm , , LKML To: Andrea Righi Return-path: In-Reply-To: <20120216005608.GC21685@thinkpad> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org On 2/15/12 4:56 PM, Andrea Righi wrote: > Oh sorry, you're right! nocache_tree is not a pointer inside > address_space, so the compiler must know the size. > > mmh... move the definition of the rb_root struct in linux/types.h? or > simply use a rb_root pointer. The (void *) looks a bit scary and too bug > prone. Either way is fine. I did some black box testing of the patch (comparing noreuse vs dontneed) and it behaves as expected. On a file copy, neither one pollutes the page cache. But if I run a random read benchmark on the source file right before and afterwards, page cache is warm with noreuse, but cold with dontneed. Copy performance was unaffected. I can't really comment on the implementation details since I haven't reviewed it, but the functionality sounds useful. -Arun -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org