MPE/iX Glossary of Terms and Acronyms (32650-90887)

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Glossary of Terms
master device A peripheral device containing the device controller board used to control
it and other slave devices.
master installation tape (MIT) A tape containing the MPE/iX operating system,
utilities, and subsystems for the HP 3000. It may be either a new version
of the software, a backup of the user's system, or the original installation
tape for a new site. MIT may also refer to a particular release of MPE.
master/slave A relation between two processes in which one initiates the execution of
the other, and controls all subsequent communications between them.
master volume A master volume is the only volume needed to define a volume set. It
contains the configuration data, the root directory, a free space map, file
label table, and a volume label with a unique volume set ID for the volume
set. See system volume.
mean time between failures (MTBF) A statistic that predicts how often failures will
occur.
mean time to recovery (MTTR) A statistic that predicts how long a certain repair
service will take.
media Devices capable of storing data, such as disks or magnetic tapes.
medium attachment unit (MAU) A device attached to a coaxial cable for a local area
network. The MAU provides physical and electrical connection from the
attachment unit interface (AUI) cable to the coaxial cable.
megabyte A measure of memory or storage space equal to 1,048,576 bytes of
characters.
member volume A volume containing a volume label indicating it belongs to an MPE/iX
volume set. It may be used by one or more volume classes.
memory An area of the computer's circuitry that holds applications and any data
generated with those applications. Information held in random access
memory (RAM) is erased whenever the computer is turned off.Information
held in read-only memory (ROM) is retained even when the computer is
off.
memory dump The contents of memory stored on disk or tape. A memory dump is
usually used for analysis and trouble shooting.
memory error logging A facility that records all memory errors. It begins automatically
when the system is initialized.
memory-mapped I/O A configuration in which each device or I/O interface card is
assigned a set of memory locations, or memory-mapped I/O registers.
menu A display on the terminal screen showing the options available within a
program. Many application programs use menus to show the options a
user can select.
message A unit of information sent from one device or computer to another in a
form that is understandable to the receiving device.
message file A special type of file with features ideal for managing messages between
processes. They also allow processes in different jobs and sessions to