American Megatrends MegaRAID Express 500 - Manual (Page 109)

Glossary 95
Glossary, Continued
Logical Disk A set of contiguous chunks on a physical disk. Logical disks are used in array
implementations as constituents of logical volumes or partitions. Logical disks
are normally transparent to the host environment, except when the array
containing them is being configured.
Logical Drive A virtual drive within an array that can consist of more than one physical drive.
Logical drives divide the contiguous storage space of an array of disk drives or a
spanned group of arrays of drives. The storage space in a logical drive is spread
across all the physical drives in the array or spanned arrays. Each MegaRAID
adapter can be configured with up to eight logical drives in any combination of
sizes. Configure at least one logical drive for each array.
Mapping The conversion between multiple data addressing schemes, especially
conversions between member disk block addresses and block addresses of the
virtual disks presented to the operating environment by Array Management
Software.
MB (Megabyte) An abbreviation for 1,000,000 (10 to the sixth power) bytes. It is the
same as 1,000 KB (kilobytes).
Multi-threaded Having multiple concurrent or pseudo-concurrent execution sequences. Used to
describe processes in computer systems. Multi-threaded processes allow
throughput-intensive applications to efficiently use a disk array to increase I/O
performance.
Operating Environment The operating environment includes the host computer where the array
is attached, any I/O buses and adapters, the host operating system, and any
additional software required to operate the array. For host-based arrays, the
operating environment includes I/O driver software for the member disks, but
does not include Array Management Software, which is regarded as part of the
array itself.
Cont’d