IBM MegaRAID 8480 manual SAS device, Sata, stripe size, striping

SAS device	Any device that conforms to the SAS standard and is attached to the
	SAS bus by a SAS cable. This includes SAS storage adapters
	(host adapters) and SAS peripherals.
SATA	Acronym for Serial Advanced Technology Attachment. A physical storage
	interface standard, SATA is a serial link that provides point-to-point
	connections between devices. The thinner serial cables allow for better
	airflow within the system and permit smaller chassis designs.
SMP	Acronym for Serial Management Protocol. SMP enables communicates
	topology management information directly with an attached SAS
	expander device. Each PHY on the controller can function as an SMP
	initiator.
SSP	Acronym for Serial SCSI Protocol. SSP enables communication with
	other SAS devices. Each PHY on the SAS controller can function as an
	SSP initiator or SSP target.
STP	Acronym for Serial Tunneling Protocol. STP enables communication with
	a SATA II device through an attached expander. Each PHY on the SAS
	controller can function as an STP initiator.
stripe size	The total disk space consumed by a stripe not including a parity disk. For
	example, consider a stripe that contains 64 Kbytes of disk space and has
	16 Kbytes of data residing on each disk in the stripe. In this case, the
	stripe size is 64 Kbytes and the stripe element size is 16 Kbytes. The
	stripe depth is four (four physical disks in the stripe). You can specify
	stripe sizes of 8 Kbytes, 16 Kbytes, 32 Kbytes, 64 Kbytes, or 128 Kbytes
	for each virtual disk. A larger stripe size produces improved read
	performance, especially if most of the reads are sequential. For mostly
	random reads, select a smaller stripe size.
striping	Disk striping writes data across two or more disks. Each stripe spans two
	or more disks but consumes only a portion of each disk. Each disk,
	therefore, may have several stripes. The amount of space consumed by
	a stripe is the same on each disk included in the stripe. The portion of
	a stripe that resides on a single disk is a stripe element. Striping by itself
	does not provide data redundancy; striping in combination with parity
	provides data redundancy.

A-4	Glossary of Terms and Abbreviations
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