Comments on: Maintaining your XFS with XFS Filesystem Reorganiser xfs_fsr to defrag

By: KevinLS

KevinLS — Thu, 17 Nov 2011 03:53:16 +0000

Looks like this article is a couple years old; but I’m sure glad I found it.

Very helpful!

Thanks!

By: Jeffrey Hundstad

Jeffrey Hundstad — Tue, 07 Jun 2011 14:12:09 +0000

Here’s a response to WHY this occurs:

http://old.nabble.com/Defragging-XFS-File-Systems-to31788982.html#a31789236

Re: Defragging XFS File Systems

by Stewart Smith-2 Jun 07, 2011; 12:48am

On Mon, 6 Jun 2011 22:52:48 -0500, Kenneth Emerson wrote:
> I hadn’t given much thought to fragmentation of my TV recordings volume
> (XFS) until reading through some MythTV-users threads recently that
> mentioned how fragmented an XFS file system could become. After running
> xfs_db, I found out that my fs appeared to be quite bad:

MythTV can end up with fragmentation on XFS due to an fsync() call that
attempts to work raound limitations in ext3.

Workarounds include:
- allocsize mount parameter
- patch mythtv source not to fsync (you could easily write a patch that
only did fsync if not xfs… I’ve been meaning to do this for
years… not enough hours in day).
- run mythbackend with libeatmydata, thus disabling the fsync

–
Stewart Smith

By: Setting up LVM on Debian | Tech Krunch

Setting up LVM on Debian | Tech Krunch — Thu, 12 Nov 2009 21:07:59 +0000

[...] Reference 4 Good guide for defraging an XFS partition: http://www.thushanfernando.com/index.php/2009/01/25/maintaining-your-xfs-with-xfs-fsr/ [...]

By: Part II: Rebuilding ZEUS – The Operating System, FileSystem & Virtualisation | Thushan Fernando Uncut

Sun, 18 Oct 2009 01:46:16 +0000

[...] which is running LVM with an XFS volume holding approximately 2.5Tb worth of data. There’s a cron job that defrags the XFS volume to keep things in [...]

By: Seth

Seth — Mon, 28 Sep 2009 23:01:00 +0000

This was excellent information indeed. I found out my VM volume was dramatically fragmented (49%) and getting very slow read performance (stretches of 10Mb/s in sequential _file_ reads, as opposed to ~70Mb/s when unfragment, i.e. sequential _disk_ reads).

It turned out I had to feed XFS some more extents for it to even start reorganizing, but then it went smooth! I’ll run xfs_fsr against the boot profile (readahead) on my ubuntu box to see what happens!

By: wilee

wilee — Wed, 09 Sep 2009 22:23:34 +0000

ubuntu myth has an option in the gui myth controller to defrag xfs , mine was at %30 when I started

By: The anatomy of the Ext4 File-System | Thushan Fernando Uncut

The anatomy of the Ext4 File-System | Thushan Fernando Uncut — Mon, 23 Feb 2009 12:21:33 +0000

[...] significant changes and updates made to Ext4 and how it differs from previous releases. I’m using XFS on my file server eagerly awating the arrival of [...]

By: chuck

chuck — Tue, 27 Jan 2009 06:14:41 +0000

hey thanks for the info i mine was 98% fragmented and now after 8 ours its down to less than 1%, please keep posting about linux stuff