setext(1)

setext (vxfs) - set extent attributes on a VERITAS File System

Synopsis

setext [-e extent_size] [-r reservation] [-f flags] file

Description

setext allows space to be reserved to a file, and a fixed extent size to be specified for a file. The file must already exist.

Options

-e extent_size

Specify a fixed extent size. The extent size is specified in file system blocks.

-r reservation

Preallocate space for a file. The reservation is specified in file system blocks.

-f flags

The available allocation flags are:

-f align: Specify that all extents must be aligned on extent_size boundaries relative to the start of allocation units.
-f chgsize: Specify that the reservation is to be immediately incorporated into the file. The file's inode is updated with size and block count information that is increased to include the reserved space. The space added to the file is not initialized. Only users with appropriate privileges can use the -f chgsize flag.
-f contig: Specify that the reservation must be allocated contiguously.
-f noextend: Specify that the file may not be extended once the preallocated space has been used.
-f noreserve: Specify that the reservation is not a persistent attribute of the file. Instead, the space is allocated until the final close of the file, when any space not used by the file is freed. The temporary reservation is not visible to the user (via getext(1)) or the VX_GETEXT ioctl, for instance).
-f trim: Specify that the reservation is trimmed to the current file size upon last close by all processes that have the file open.

Notices

setext is available with the VxFS Advanced feature set only.

Multiple flags may be specified by specifying multiple instances of -f in a command line.

The allocation flags must be specified along with either the -e or -r option.

The align and noextend allocation flags are persistent attributes of the file and therefore visible via getext(1) or the VX_GETEXT ioctl. Although trim is not a persistent attribute of the file, it is visible until it is cleared during the final close of the file. Other allocation flags may have persistent effects, but are not visible as allocation flags.

Under certain circumstances, fsadm_vxfs(1M) may reorganize the extent map of a file in such a way as to make it less contiguous. However, it will not change the geometry of a file that has a fixed extent size.

References

getext(1), fsadm_vxfs(1M), vxfsio(7)