xfsgrowfs

xfsgrowfs is a commonly used notation for the Linux command-line tool xfs_growfs, which is used to enlarge an XFS filesystem. It is part of the xfsprogs package and is designed to perform online filesystem growth on mounted volumes.

XFS filesystems can be grown while mounted, meaning the operation does not require unmounting the filesystem. Growth increases the space available in the filesystem to utilize free space on the underlying block device, such as after extending a partition or logical volume. The underlying device must have additional available space for growth to succeed.

Usage typically involves invoking the tool with the mount point of the filesystem. The most common form is xfs_growfs /mount-point, which expands the filesystem to the maximum size of the underlying block device. The -D option can be used to specify a particular target size for the data portion of the filesystem, given in 512-byte blocks. For example, -D 200000 sets the data capacity to 200,000 blocks. If -D is omitted, growth proceeds to the device’s available space. Root privileges or equivalent capabilities are required to perform the operation.

Limitations include that XFS cannot be shrunk with xfs_growfs; to reduce a filesystem, you must back up data, recreate the filesystem at a smaller size, and restore. Growth is also dependent on the host recognizing and exposing additional space on the block device, and may interact with layered storage configurations (such as LVM or hardware RAID).

In summary, xfsgrowfs/xfs_growfs is the standard tool for online expansion of XFS filesystems, providing a straightforward means to increase usable space without taking the filesystem offline.