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.
The tools to manage XFS partions are in the official repositories, which is included in the default base installation.package from the
If for whatever reason you experience data corruption, you will need to repair the filesystem manually.
Repair XFS Filesystem
First unmount the XFS filesystem.
# umount /dev/sda3
Once unmounted, run the xfs_repair tool.
# xfs_repair -v /dev/sda3
xfsprogs 3.2.0 has introduced a new on-disk format (v5) that includes a metadata checksum scheme called Self-Describing Metadata.
Based upon CRC32 it provides for example additional protection against metadata corruption during unexpected power losses. Checksum is enabled by default when using xfsprogs 3.2.3 or later. If you need read-write mountable xfs for older kernel, It can be easily disable using the
-m crc=0 switch when calling mkfs.xfs.
# mkfs.xfs -m crc=0 /dev/target_partition
The XFS v5 on-disk format is considered stable for production workloads starting Linux Kernel 3.15.
For optimal speed, just create an XFS file system with:
# mkfs.xfs /dev/target_partition
Yep, so simple - since all of the "boost knobs" are already "on" by default.
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
You can increase performance by disabling barrier usage for the filesystem by adding the nobarrier mount option to the
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.
nodiratime, so there is never a need to specify nodiratime when noatime is also specified.
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
To begin defragmentation, use the
xfs_fsr command which is included with the xfsprogs package.
# xfs_fsr /dev/sda3
Free inode btree
Starting Linux 3.16, XFS has added a btree that tracks free inodes. It is equivalent to the existing inode allocation btree with the exception that the free inode btree tracks inode chunks with at least one free inode. The purpose is to improve lookups for free inode clusters for inode allocation. It improves performance on aged filesystems i.e. months or years down the track when you have added and removed millions of files to/from the filesystem. Using this feature doesn't impact overall filesystem reliability level or recovery capabilities.
This feature relies on the new v5 on-disk format that has been considered stable for production workloads starting Linux Kernel 3.15. It does not change existing on-disk structures, but adds a new one that must remain consistent with the inode allocation btree; for this reason older kernels will only be able to mount read-only filesystems with the free inode btree feature.
The feature enabled by default when using xfsprogs 3.2.3 or later. If you need writable filesystem for older kernel, it can be disable with
finobt=0 switch when formatting a XFS partition. You will need
# mkfs.xfs -m crc=0,finobt=0 /dev/target_partition
or shortly (
# mkfs.xfs -m crc=0 /dev/target_partition