Hitachi AMS 2000 User Manual page 220

C
cache
A temporary, high-speed storage mechanism. It is a reserved section of
main memory or an independent high-speed storage device. Two types
of caching are found in computers: memory caching and disk caching.
Memory caches are built into the architecture of microprocessors and
often computers have external cache memory. Disk caching works like
memory caching; however, it uses slower, conventional main memory
that on some devices is called a memory buffer.
capacity
The amount of information (usually expressed in megabytes) that can
be stored on a disk drive. It is the measure of the potential contents of
a device; the volume it can contain or hold. In communications,
capacity refers to the maximum possible data transfer rate of a
communications channel under ideal conditions.
CCI
See command control interface.
CLI
See command line interface.
cluster
A group of disk sectors. The operating system assigns a unique number
to each cluster and then keeps track of files according to which clusters
they use.
cluster capacity
The total amount of disk space in a cluster, excluding the space
required for system overhead and the operating system. Cluster
capacity is the amount of space available for all archive data, including
original file data, metadata, and redundant data.
command control interface (CCI)
Hitachi's Command Control Interface software provides command line
control of Hitachi array and software operations through the use of
commands issued from a system host. Hitachi's CCI also provides a
scripting function for defining multiple operations.
command devices
Dedicated logical volumes that are used only by management software
such as CCI, to interface with the storage systems. Command devices
are not used by ordinary applications. Command devices can be shared
between several hosts.
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Hitachi AMS 2000 Family TrueCopy Extended Distance User Guide
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