HP Surestore Disk Array FC60 HP SureStore E Disk Array FC60 - (English) Advanc - Page 453

SIMM (Single In-line Memory Module) A memory module that provides the local storage (cache) for an SP. An SP must have at least two 4-MB memory modules to support the storage system cache. Start Of Day (SOD) The initialization process used by the disk array controllers to configure itself and establish various operating parameters. Each controller runs its own SOD process. The SOD process occurs following a power on reset, or following the insertion of a controller. status light Lights on the front panel of each disk module, power module, and fan used to indicate the operating status of the hardware. STM (Support Tools Manager) A host-based tool used for disk array configuration, management, and diagnostics. stripe boundary crossing In disk striping, if the stripe segment size is too small for a single I/O operation, the operation requires access to two stripes. Called a stripe boundary crossing, this event reduces I/O performance. stripe segment size The amount of information simultaneously read from or written to each disk in a LUN using disk striping. The default stripe segment size is set to the same value used for cache page size (4K or 16K). The stripe segment size is configurable and can affect I/O performance. If the segment size for the LUN is set too small, it may result in many stripe boundary crossings. striping (disk striping) See disk striping. terminator An electrical connection at each end of the SCSI bus composed of a set of resistors (or possibly other components). Its function is to provide a pull-up for open-collector 453 Glossary