XFS
XFS is a high-performance journaling file system created by Silicon Graphics, Inc. XFS is particularly proficient at parallel IO due to its allocation group based design. This enables extreme scalability of IO threads, filesystem bandwidth, file and filesystem size when spanning multiple storage devices.
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Installation
In order to manage XFS partitions, install xfsutils from the official repositories.
Data corruption
If for whatever reason you experience data corruption, you will need to repair the filesystem manually.
Repair XFS Filesystem
First unmount the XFS filesystem.
# unmount /dev/sda3
Once unmounted, run the xfs_repair tool.
# xfs_repair -v /dev/sda3
Performance
The best way to get performance out of XFS is to plan ahead before you create the filesystem. Where is the journal stored?
For more info read: Maximizing Performance
Stripe size and width
If this filesystem will be on a striped RAID you can gain significant speed improvements by specifying the stripe size to the mkfs.xfs command.
See How to calculate the correct sunit,swidth values for optimal performance
Disable barrier
You can increase performance by disabling barrier usage for the filesystem by adding the nobarrier mount option to the /etc/fstab file.
Access time
On some filesystems you can increase performance by adding the noatime mount option to the /etc/fstab file. For XFS filesystems the default atime behaviour is relatime, which has almost no overhead compared to noatime but still maintains sane atime values. All Linux filesystems use this as the default now (since around 2.6.30), but XFS has used relatime-like behaviour since 2006, so no-one should really need to ever use noatime on XFS for performance reasons.
Also, noatime implies nodiratime, so there is never a need to specify nodiratime when noatime is also specified.
Defragmentation
Although the extent-based nature of XFS and the delayed allocation strategy it uses significantly improves the file system's resistance to fragmentation problems, XFS provides a filesystem defragmentation utility (xfs_fsr, short for XFS filesystem reorganizer) that can defragment the files on a mounted and active XFS filesystem. It can be useful to view XFS fragmentation periodically.
xfs_fsr improves the organization of mounted filesystems. The reorganization algorithm operates on one file at a time, compacting or otherwise improving the layout of the file extents (contiguous blocks of file data).
Inspect fragmentation levels
To see how much fragmentation your file system currently has:
# xfs_db -c frag -r /dev/sda3
Perform defragmentation
To begin defragmentation, use the xfs_fsr command which is included with the xfsprogs package.
# xfs_fsr /dev/sda3