System information

Examp le 8.1. mkfs. xfs co mmand ou t p u t
Below is a sample output of the mkfs. xfs command:
meta-data=/dev/device isize=256 agcount=4, agsize=3277258
blks
= sectsz=512 attr=2
data = bsize=4096 blocks=13109032,
imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0
log =internal log bsize=4096 blocks=6400, version=2
= sectsz=512 sunit=0 blks, lazy-
count=1
realtime =none extsz=4096 blocks=0, rtextents=0
Note
After an XFS file system is created, its size cannot be reduced. However, it can still be enlarged
using the xfs_g ro wfs command (refer to Section 8.4, “ Increasing the Size of an XFS File
System” ).
For striped block devices (for example, RAID5 arrays), the stripe geometry can be specified at the time
of file system creation. Using proper stripe geometry greatly enhances the performance of an XFS
filesystem.
When creating filesystems on LVM or MD volumes, mkfs. xfs chooses an optimal geometry. This
may also be true on some hardware RAIDs that export geometry information to the operating system.
To specify stripe geometry, use the following mkfs. xfs sub-options:
su= value
Specifies a stripe unit or RAID chunk size. The value must be specified in bytes, with an
optional k, m, or g suffix.
sw= value
Specifies the number of data disks in a RAID device, or the number of stripe units in the
stripe.
The following example specifies a chunk size of 64k on a RAID device containing 4 stripe units:
# mkfs. xfs -d su= 64 k,sw= 4 /d ev/device
For more information about creating XFS file systems, refer to man mkfs. xfs.
8.2. Mount ing an XFS File Syst em
An XFS file system can be mounted with no extra options, for example:
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