HP-UX System Administrator's Guide: Overview HP-UX 11i v3 (B3921-90011, September 2010)

For More Information on Configuring and Managing Swap Space
The following manpages contain important information on configuring swap space:
fstab(4)
The file /etc/fstab not only defines which file systems should be mounted
to which mount points in the directory tree (see “The HP-UX Directory
Structure” (page 40)), it is also one of the key places you configure swap
space.
lvlnboot(1M)
lvlnboot prepares an LVM logical volume to be root, boot, primary swap,
or a dump volume.
swapinfo(1M)
swapinfo prints information about device and file system paging space.
swapon(1M)
The swapon command enables devices or file systems on which paging is
to take place.
swapoff(1M)
The swapoff command disables active paging areas, if possible.
The following kernel tunables affect paging activities on HP-UX:
nswapdev
Maximum number of swap devices that can be enabled for swap.
HP-UX Input and Output
Input and Output (I/O) on HP-UX is accomplished by reading from and writing to special files
known as device special files. Starting with HP-UX 11i version 3, there are two types of device
special files:
• Legacy Device Special Files
• Persistent Device Special Files
Persistent device special files offer many advantages over legacy device special files:
• With legacy device special files, if you move the device associated with them (logically or
physically) you will need to address those devices via new or different device special files.
This is because the device special files are associated with the physical path to the device (the
sequence of internal components that data must travel). If any part of the path changes, a
different device special file is needed.
• Persistent device special files are instead associated with a unique address on the device (known
as a worldwide identifier — WWID) rather than the path to the device. This means that even
if the path to the device changes, no changes are needed to the device special files associated
with that device.
Persistent device special files are only associated with mass storage devices. Generally these
are disk drives, some tape drives, and similar mass storage devices.
For non-mass storage devices, the traditional form of device special files (based on hardware
paths as with legacy device special files for mass storage devices) still applies.
For more information on device special files, “How Storage is Addressed”.
Printing
Printing on HP-UX is accomplished through a subsystem known as the HP-UX Line Printer
Spooling System.
Overview of the HP-UX Line Printer Spooling System
The Line Printer Spooling System (spooler) is a set of programs, shell scripts, and directories that
controls your printers and the flow of data going to them.
64 Major Components of HP-UX