Veritas File System 4.1 Administrator's Guide (HP-UX 11i v3, February 2007)

Chapter 10 135
10 Quality of Storage Service
The VERITAS File System allows you to create a file system that spans multiple volumes ,known as a
multi-volume file system. The component volumes compose a volume set. See “Quality of Storage Service”
on page 135. On top of this basic capability is a set of services known as Quality of Storage Service (QoSS).
Using different volumes you can enhance the performance of applications, that access specific types of files,
using different volumes and managing where the types of files are located.For example, if you have files that
are infrequently accessed, you can place them on slower media that is relatively inexpensive, but which has
a slower access time.
You can configure policies that automatically relocate files from one volume to another, or you can relocate
files by running file relocation commands.The QoSS has two parts:
• Relocation policies: Policies that you configure to determine which files to move to a different
component volume.
• File relocation: The fssweep utility recursively examines a multi-volume file system by searching for
files that match configured relocation policies. After searching a file system, fssweep passes
information about files that match policies to the fsmove utility. The fsmove utility reads a list of file
names and locations that fssweep has created and relocates files based on that relocation list.
NOTE VERITAS Quality of Storage Service is a licensed feature.You must purchase a separate
license key to enable the QoSS feature.See the VERITAS File System Release Notes for
current product information.