System Startup, Configuration, and Shutdown Reference Manual (32650-90907)

Glossary
throughput
Glossary
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throughput A measurement of a computer system’s
speed and productivity.
transaction A logical unit of work.
transaction logging A method of tracking each
unit of work to facilitate recovery from the abnormal
end of transaction processing and system failures. A
transaction log file is automatically generated and
maintained by the transaction management facility.
Files can be restored to a consistent state by copying
the contents of the log file into the data file.
transient space Disk space used for temporary
processes such as stacks and operating system data
structures.
unit number A part of an address used for devices.
A number whose meaning is software-dependent
and device-dependent, but which is often used to
specify a particular disk drive in a device with a
multidrive controller.
UPDATE 1) The MPE/iX ISL utility that performs a
system load from tape. It replaces the current base
system files on disk, and optionally replaces
configuration files. The ISL UPDATE
CONFIG option is equivalent to the MPE V/E
COLDSTART procedure, and the UPDATE NOCONFIG
option is equivalent to the MPE V/E UPDATE
operation. 2) An MPE V/E coldload option that loads
all files in the PUB group of the SYS account from the
backup media. I/O configuration data, the directory,
and user files are loaded from the system disk.
UPDATE is typically used to install a new version of
system software or to load MPE from another
computer. Equivalent to the MPE/iX ISL UPDATE
utility UPDATE NOCONFIG option.
use communications subsystems capability
(CS capability) A capability assigned to accounts
and users allowing access to the MPE
communications subsystems.
user command A set of MPE/iX commands that a
user has grouped together to perform a specific task.
A user command is stored in a command file and
does not have to be entered into a catalog. User
commands are last in MPE’s search path for
commands.
user level security The file access modes
permitted the user. User level security must
duplicate, or be a subset of, the file access permitted
the user's account and group.
user logging A facility that enables users and
subsystems to record additions and modifications to
files. If necessary, user logging also provides the
means whereby recorded entries can be used to
recover the files themselves.
use volumes capability (UV capability) A
capability assigned at the account and user level
allowing users to access private disk volumes.
utility program An operating system program that
performs specific functions such as file copying,
sorting, merging, memory dump analysis, or
monitoring available disk space.
variable A value that can be changed, as opposed to
a constant, usually represented by a letter or a group
of alphanumeric characters.
volume A single disk pack. Each volume is a
member of a volume set and contains a volume label,
a label table, and a free space map.
volume class A class used for the allocation and
restriction of disk space. A volume class is a logical
subset or partition within a volume set and can
bridge any number of physical member volumes of a
volume set.
volume name The name given to a volume set or
volume class with the NEWSET command. The name
can be assigned only by a user with CV (create
volume) capability, usually the system manager or
account manager. The volume name is an ASCII
character string of up to eight alphanumeric
characters, beginning with an alphabetic character.
volume number The part of an address used for a
device number whose meaning is software and
device dependent, but is often used to specify a
particular volume on a multivolume disk drive.
volume set A group of up to 255 related disk packs.
One volume of the volume set must be designated as
the master volume for the set. Each volume set is
assigned a name by which it is identified and
referenced. MPE/iX recognizes both system volume
sets and nonsystem, or mountable, volume sets.