HP JFS 3.3 and HP OnLineJFS 3.3 VERITAS File System 3.3 System Administrator's Guide

26 Chapter1
The VxFS File System
Extent Attributes
Extent Attributes
VxFS allocates disk space to files in groups of one or more extents. HP
OnLineJFS also allows applications to control some aspects of the extent
allocation. Extent attributes are the extent allocation policies
associated with a file.
The setext and getext commands allow the administrator to set or
view extent attributes associated with a file, as well as to preallocate
space for a file. Refer to Chapter 3 , “Extent Attributes,” Chapter 6 ,
“Application Interface,” setext(1M), and getext(1M) for discussions on
how to use extent attributes.
The vxtunefs command allows the administrator to set or view the
default indirect data extent size. Refer to Chapter 5 , “Performance and
Tuning” and vxtunefs(1M) for discussions on how to use the indirect
data extent size feature.
NOTE setext functionality is available only with the optional HP OnLineJFS
product.