VERITAS Storage Foundation 4.1 Oracle Administrator's Guide

Glossary 533
Prerelease 8 September 2005, 8:55am
stripe
A set of stripe units that occupy the same positions across a series of columns in a multi-disk
layout.
stripe unit
Equally sized areas that are allocated alternately on the subdisks (within columns) of each striped
plex. In an array, this is a set of logically contiguous blocks that exist on each disk before
allocations are made from the next disk in the array. A stripe unit may also be referred to as a stripe
element.
stripe unit size
The size of each stripe unit. The default stripe unit size is 32 sectors (16K). A stripe unit size has
also historically been referred to as a stripe width.
striping
A layout technique that spreads data across several physical disks using stripes. The data is
allocated alternately to the stripes within the subdisks of each plex.
subdisk
A consecutive set of contiguous disk blocks that form a logical disk segment. Subdisks can be
associated with plexes to form volumes.
superuser
A user with unlimited access privileges who can perform any and all operations on a computer. In
UNIX, this user may also be referred to as the “root” user. On Windows/NT, it is the
“Administrator.”
System Global Area
The area of memory used for database information shared by all database users. Each SGA contains
the data and control information for a single Oracle instance.
tablespace
In an Oracle database, an allocation of space used to hold schema objects (triggers, stored
procedures, tables, etc.). A tablespace is associated with one or more datafiles.
terabyte
Shorthand for 1,000,000,000,000 (10
12
) bytes (or approximately 1000 GB).