From mboxrd@z Thu Jan 1 00:00:00 1970 From: Li Wang Subject: Re: [PATCH 0/5] VFS: Directory level cache cleaning Date: Tue, 17 Dec 2013 11:08:16 +0800 Message-ID: <52AFC020.10403@ubuntukylin.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Alexander Viro , Sage Weil , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, LKML , Yunchuan Wen To: Cong Wang Return-path: In-Reply-To: Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org As far as we know, fadvise(DONTNEED) does not support metadata cache cleaning. We think that is desirable under massive small files situations. Another thing is that do people accept the behavior of feeding a directory fd to fadvise will recusively clean all page caches of files inside that directory? On 2013/12/17 1:45, Cong Wang wrote: > On Mon, Dec 16, 2013 at 7:00 AM, Li Wang wrote: >> This patch extend the 'drop_caches' interface to >> support directory level cache cleaning and has a complete >> backward compatibility. '{1,2,3}' keeps the same semantics >> as before. Besides, "{1,2,3}:DIRECTORY_PATH_NAME" is allowed >> to recursively clean the caches under DIRECTORY_PATH_NAME. >> For example, 'echo 1:/home/foo/jpg > /proc/sys/vm/drop_caches' >> will clean the page caches of the files inside 'home/foo/jpg'. >> > > This interface is ugly... > > And we already have a file-level drop cache, that is, > fadvise(DONTNEED). Can you extend it if it can't > handle a directory fd? > -- 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 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752742Ab3LQDQH (ORCPT ); Mon, 16 Dec 2013 22:16:07 -0500 Received: from m59-178.qiye.163.com ([123.58.178.59]:52560 "EHLO m59-178.qiye.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752026Ab3LQDQF (ORCPT ); Mon, 16 Dec 2013 22:16:05 -0500 Message-ID: <52AFC020.10403@ubuntukylin.com> Date: Tue, 17 Dec 2013 11:08:16 +0800 From: Li Wang User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Thunderbird/24.1.1 MIME-Version: 1.0 To: Cong Wang CC: Alexander Viro , Sage Weil , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, LKML , Yunchuan Wen Subject: Re: [PATCH 0/5] VFS: Directory level cache cleaning References: In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-HM-Spam-Status: e1koWUFPN1dZCBgUCR5ZQUlIVUNLQkJCQk9NTkJPSUhDSFdZCQ4XHghZQV koKz0kKDQ9Lz06MjckMjUkMz46Pz4pQUtVS0A2IyQiPigkMjUkMz46Pz4pQUtVS0ArLykkNTQkMj UkMz46Pz4pQUlVS0A4NC41LykiJDg1QUtVS0ApPjwyNDUkOigyOkFLVUtAKyk0LTI1OD4kMy41Oj VBS1VLQD8iNTo2MjgkMiskNTQkMjUkMz46Pz4pQUtVS0ApPjo3JDIrJDI1JCk5NyQyNSQzPjo*Pi lBSklVS0A2LjcvMiQpOCsvJD8yPT0#KT41LyQyNSQzPjo*PilBSVVLQDIrJC80PzoiJDg1LyRLJE pLS0FLVUtAMiskTiQ2MjUuLz4kODUvJEskSktBS1VLQDIrJEokNjI1Li8#JDg1LyRLJEpLQUtVS0 AyKyRKJDM0LikkODUvJEskSktLQUtVS0AyKyRISyQ2MjUuLz4kODUvJEskTktBS1VLQDU0LyQ9Oj Y0LigkPzQ2OjI1JCgrPSQ9OjI3QUpLVUtAPTUkNjoiJE9KQiQzNzEkSiRLQ0tIS09BS1VISEA9Ky QpPiQ9LCQzNzEkS0NLSEtNQVZMVU5AKC45JD5BSlVOTkA9NSQoLjkkPjUsNCk*KCQzNzEkSktLSU tKQUtVSUNAPTUkOTIvTCQzNzEkS0xKSUtJQUhVSk5ZBg++ X-HM-Sender-Digest: e1kSHx4VD1lBWUc6MQg6Cjo4LDo4EDorKjhIOj4qOkMwCjFVSlVKSENM SU9CTEtLTUJNVTMWGhIXVRcSDBoVHDsOGQ4VDw4QAhcSFVUYFBZFWVdZDB4ZWUEdGhcIHldZCAFZ QUlOQ0s3V1kSC1lBWU1KVUpDTFVOT1VCWQY+ Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As far as we know, fadvise(DONTNEED) does not support metadata cache cleaning. We think that is desirable under massive small files situations. Another thing is that do people accept the behavior of feeding a directory fd to fadvise will recusively clean all page caches of files inside that directory? On 2013/12/17 1:45, Cong Wang wrote: > On Mon, Dec 16, 2013 at 7:00 AM, Li Wang wrote: >> This patch extend the 'drop_caches' interface to >> support directory level cache cleaning and has a complete >> backward compatibility. '{1,2,3}' keeps the same semantics >> as before. Besides, "{1,2,3}:DIRECTORY_PATH_NAME" is allowed >> to recursively clean the caches under DIRECTORY_PATH_NAME. >> For example, 'echo 1:/home/foo/jpg > /proc/sys/vm/drop_caches' >> will clean the page caches of the files inside 'home/foo/jpg'. >> > > This interface is ugly... > > And we already have a file-level drop cache, that is, > fadvise(DONTNEED). Can you extend it if it can't > handle a directory fd? >