From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Sun, 25 May 2008 04:38:05 -0700 (PDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.168.28]) by oss.sgi.com (8.12.11.20060308/8.12.11/SuSE Linux 0.7) with ESMTP id m4PBc2Rp015800 for ; Sun, 25 May 2008 04:38:02 -0700 Received: from mail.lichtvoll.de (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 309B01226C60 for ; Sun, 25 May 2008 04:38:52 -0700 (PDT) Received: from mail.lichtvoll.de (mondschein.lichtvoll.de [194.150.191.11]) by cuda.sgi.com with ESMTP id SFaTBE2YmCnW0jaH for ; Sun, 25 May 2008 04:38:52 -0700 (PDT) Received: from [10.0.0.21] (g228074001.adsl.alicedsl.de [92.228.74.1]) by mail.lichtvoll.de (Postfix) with ESMTP id 8D94A5AE29 for ; Sun, 25 May 2008 13:38:50 +0200 (CEST) From: Martin Steigerwald Subject: Re: XFS for lots of small files Date: Sun, 25 May 2008 13:38:48 +0200 References: <4820832B.3070903@dubielvitrum.pl> <200805062055.36755.Martin@lichtvoll.de> <4838DC1A.5010206@sandeen.net> (sfid-20080525_131427_063047_18AAAB7D) In-Reply-To: <4838DC1A.5010206@sandeen.net> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-2" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200805251338.48910.Martin@lichtvoll.de> Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com List-Id: xfs To: linux-xfs@oss.sgi.com Am Sonntag 25 Mai 2008 schrieb Eric Sandeen: > Martin Steigerwald wrote: > > And there is quite some fragmentation on it: > > > > xfs_db> frag > > actual 653519, ideal 587066, fragmentation factor 10.17% > > No, there's not. OK, so there is or better was (see below) *some* fragmentation. > You have 653519 extents out of an "ideal" 587066. > > That is 653519/587066 = 1.113 extents per file. > > It is not "quite some" fragmentation, it is near perfect (although this > is subjective, and also depends on the size of your files... if they > are all 8k then 1.113 extents per file might be a bit high; if they > average 1G then 1.113 extents on average is pretty darned good.) They vary a lot. From KMail ~/Mail directory with hundred of thousands of mails in maildir format to a picture and movie collection from various digicams with 150KB over 2-4 MB to 50-200 MB in size and a music collection and kernel sources and and and... would need to run a tool on them to gather some statistic. Anyway, nothing that can't be optimized: shambala> xfs_db -r /dev/sda5 xfs_db> frag actual 683648, ideal 617593, fragmentation factor 9.66% xfs_db> quit shambala> xfs_fsr /dev/sda5 /home start inode=0 shambala> xfs_db -r /dev/sda5 xfs_db> frag actual 620316, ideal 617584, fragmentation factor 0.44% xfs_db> quit xfs_fsr copied over several gigabytes and the free space of the partition temporarily more than once was 4 GB less than the 20 GB of free space it had before and after invoking xfs_fsr ;) Not that I noticed a difference up to now however. Ciao, -- Martin 'Helios' Steigerwald - http://www.Lichtvoll.de GPG: 03B0 0D6C 0040 0710 4AFA B82F 991B EAAC A599 84C7