LSI 25083 manual SAS device, 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 RAID controllers
	(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 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 drive space consumed by a stripe not including a parity drive.
	For example, consider a stripe that contains 64 Kbytes of drive space
	and has 16 Kbytes of data residing on each drive 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 drives in the stripe). You can
	specify stripe sizes of 8 Kbytes, 16 Kbytes, 32 Kbytes, 64 Kbytes,
	128 Kbytes, 256 Kbytes, 512 Kbytes, or 1 Mbyte for each virtual drive.
	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	Drive striping writes data across two or more drives. Each stripe spans
	two or more drives but consumes only a portion of each drive. Each
	drive, therefore, may have several stripes. The amount of space
	consumed by a stripe is the same on each drive that is included in the
	stripe. The portion of a stripe that resides on a single drive 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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