From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753068Ab2LXIXN (ORCPT ); Mon, 24 Dec 2012 03:23:13 -0500 Received: from mail-pb0-f52.google.com ([209.85.160.52]:48942 "EHLO mail-pb0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752946Ab2LXIXK (ORCPT ); Mon, 24 Dec 2012 03:23:10 -0500 Date: Mon, 24 Dec 2012 16:36:37 +0800 From: Zheng Liu To: Andy Lutomirski Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Linux FS Devel , Dave Chinner , Jan Kara , Al Viro Subject: Re: [PATCH v2 2/3] mm: Update file times when inodes are written after mmaped writes Message-ID: <20121224083637.GA11906@gmail.com> Mail-Followup-To: Andy Lutomirski , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Linux FS Devel , Dave Chinner , Jan Kara , Al Viro References: <6b22b806806b21af02b70a2fa860a9d10304fc16.1356124965.git.luto@amacapital.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <6b22b806806b21af02b70a2fa860a9d10304fc16.1356124965.git.luto@amacapital.net> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 21, 2012 at 01:28:27PM -0800, Andy Lutomirski wrote: > The onus is currently on filesystems to call file_update_time > somewhere in the page_mkwrite path. This is unfortunate for three > reasons: > > 1. page_mkwrite on a locked page should be fast. ext4, for example, > often sleeps while dirtying inodes. (This could be considered a > fixable problem with ext4, but this approach makes it > irrelevant.) Hi Andy, Out of curiosity, could you please share more detailed information about how to reproduce and measure this problem in ext4? Thanks - Zheng