From mboxrd@z Thu Jan 1 00:00:00 1970 From: geearf@free.fr Subject: Re: Reiser4 Fragmentation Date: Tue, 17 Feb 2009 01:14:32 +0100 (CET) Message-ID: <1385878997.819661234829671975.JavaMail.root@zimbra4-e1.priv.proxad.net> References: <493286232.819611234829500161.JavaMail.root@zimbra4-e1.priv.proxad.net> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <493286232.819611234829500161.JavaMail.root@zimbra4-e1.priv.proxad.net> Sender: reiserfs-devel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Edward Shishkin Cc: reiserfs-devel ----- Mail Original ----- "Edward Shishkin" wrote: >geearf@free.fr wrote: >Hello. >measurefs.reiser4 is pretty ancient, and I guess >that it works incorrectly for compressed files. >(External) fragmentation resulted in a number of "extents" is >a sticky thing inherent to all linux file systems, including reiser4. >Currently there is no tools to reorganize reiser4 without having >a spare partition. However, it is possible to create something >simple like xfs_fsr: it would be an appreciable help. >The "smart reiser4 repacker" based on the flush algorithm was >supposed to be the paid option, and therefore there are some >obvious issues of its development. >Internal fragmentation, resulted in wasteful space utilization >("holes" in the metadata blocks") would mean a bug in the code. >This fragmentation can be measured as 1 minus the fraction >du (1) / df (1). Note, that du (1) should be applied to the semantic >root. If you have ccreg40 partition, then check it with >"fsck.reiser4 --fix" prior using du (1). Also make sure (for example >with sync (1)) that there is no dirty pages prior using df (1). >If the internal fragmentation is more then 0.02, while du (1) is >large enough (> 100 000), then, please, report. >Thanks, >Edward. Well I ended up taring my /, mkfs and untaring it. So it should not be fragmented in any way anymore. I will look at the internal fragmentation of my /home, but this is not under ccreg40. I've also just looked at the xfs_fsr thing and it looks pretty useful. Can't that be done with a simple script? (sort of like Con's defrag script) or does it need to be related to R4 ? Thanks Edward, John