Glossary
SuperLoader User’s Guide 269
performance
A measure of the speed of the drive during normal
operation. Factors affecting performance are seek times, transfer rate, and
command overhead.
peripheral A device added to a system as a complement to the basic
central processing unit (CPU), such as a disk drive, tape drive, or printer.
POH Power-on Hours. The unit of measurement for mean time between
failure (MTBF), expressed as the number of hours that the drive is
powered on. See MTBF.
POST Power-on Self Test. Diagnostics programs, loaded automatically
by the BIOS, that perform basic tests on the major system components,
such as memory, cartridge and magazine information. If no problems are
detected during POST, the system continues the start-up process.
PRML See Partial Response, Maximum Likelihood.
Q
QIC Quarter Inch Cartridge. A tape storage subsystem that uses
0.25 inch (6.35 mm) wide media.
R
RAM Random Access Memory. an integrated circuit memory chip that
allows information to be stored and retrieved by a microprocessor or
controller. The information can be stored or accessed in any order, and all
storage locations are equally accessible.
RAIT Redundant Array of Independent Tape Drives
random access The ability to directly locate any piece of data without
having to read everything in memory or on disk.
read after write A mode of operation that has the computer read back
each data block immediately after it is written on the tape, checking that
the data read back is the same as recorded.
read/write head The mechanism by which data is recorded onto magnetic
media in a tape drive system. See read after write.
Reed-Solomon error correction An error correction technique based on
research done by Irving reed and Gustave Solomon at MIT’s lincoln
Laboratory in the 1960s. First used to check the accuracy of data received
from the Voyager spacecraft.
restore To replace data on the hard drive from another media source.
ROM Read Only Memory. Integrated circuit chip containing programs
and data that can be accessed and read but cannot be modified.
To Next Page
Loading...
Need help?
General
