From mboxrd@z Thu Jan 1 00:00:00 1970 From: Artem Bityutskiy Subject: Re: [PATCH RESEND] ubifs: Introduce a mount option of force_atime. Date: Tue, 09 Jun 2015 09:36:49 +0300 Message-ID: <1433831809.28854.17.camel@sauron.fi.intel.com> References: <1433758060-18614-1-git-send-email-yangds.fnst@cn.fujitsu.com> Reply-To: dedekind1@gmail.com Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: linux-mtd@lists.infradead.org, adrian.hunter@intel.com, richard@nod.at, linux-fsdevel@vger.kernel.org To: Dongsheng Yang Return-path: Received: from mga03.intel.com ([134.134.136.65]:15261 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751344AbbFIGg4 (ORCPT ); Tue, 9 Jun 2015 02:36:56 -0400 In-Reply-To: <1433758060-18614-1-git-send-email-yangds.fnst@cn.fujitsu.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Mon, 2015-06-08 at 18:07 +0800, Dongsheng Yang wrote: > Currently, ubifs does not support access time anyway. I understand > that there is a overhead to update inode in each access from user. > > But for the following two reasons, I think we can make it optional > to user. > > (1). More and more flash storage in server are trying to use ubifs, > it is not only for a device such as mobile phone any more, we want > to use it in more and more generic way. Then we need to compete > with some other main filesystems. From this point, access time is > necessary to us, at least as a choice to user currently. > > (2). The default mount option about atime is relatime currently, > it's much relaxy compared with strictatime. Then we don't update > the inode in any accessing. So the overhead is not too much. > It's really acceptable. > > Signed-off-by: Dongsheng Yang > --- > It's a RESEND patch to cc to fsdevel as Artem suggested. > I would rename force_atime to enable_atime in next version. Why do you need to introduce a custom "force_atime" option if there are already standard "atime" and "noatime" mount option? I am fine with adding atime support to UBIFS in general, and I'd expect this behavior then. 1. mount -t ubifs ... - no atime by default 2. mount -t ubifs -o noatime ... - same as above 3. mount -t ubifs -o atime - support atime 4. mount -t ubifs -o rlatime - support relatime and so on for as many atime update strategies you want to support.