From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sandeen.net ([63.231.237.45]:59104 "EHLO sandeen.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725821AbeJGEZi (ORCPT ); Sun, 7 Oct 2018 00:25:38 -0400 Subject: Re: Which fragmentation factor is allowable for xfs (not impact on performance)? References: From: Eric Sandeen Message-ID: <57e256e5-bcf7-c6ce-601a-64263606d707@sandeen.net> Date: Sat, 6 Oct 2018 16:20:48 -0500 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Mikhail Gavrilov , linux-xfs@vger.kernel.org On 10/6/18 12:34 PM, Mikhail Gavrilov wrote: > Which fragmentation factor is allowable for xfs (not impact on performance)? > > # xfs_db -c frag -r /dev/sda > actual 4908781, ideal 2801391, fragmentation factor 42.93% Ignore the fragmentation factor, because: > Note, this number is largely meaningless. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ http://xfs.org/index.php/XFS_FAQ#Q:_The_xfs_db_.22frag.22_command_says_I.27m_over_50.25._Is_that_bad.3F > Files on this filesystem average 1.75 extents per file The majority of your files have only 1 extent. > # mount | grep sda > /dev/sda on /home type xfs (rw,relatime,seclabel,attr2,inode64,noquota) > > # df -h | grep sda > /dev/sda 11T 5.3T 5.7T 49% /home > > I think it too much for partition which are half free. Why do you think that? > It would also be interesting to see the fragmentation in the context > of files, but I have not found anywhere how to look at it. xfs_bmap will show you extent layout for individual files. -Eric