Table of Contents
Advertisement
SMP
SMP
Acronym for Serial Management Protocol. SMP communicates topology management
information directly with an attached SAS expander device. Each PHY on the adapter can
function as an SMP initiator.
spanning
A method for combining multiple drives into a single logical drive. If you want to have all of
the drive capacity in one drive group, you can span (merge) the drives so that the operating
system sees just one large drive. For more information, refer to the MegaRAID SAS Software
User's Guide, located at: http://www.lsi.com/sep/Pages/oracle/index.aspx.
SSP
Acronym for Serial SCSI Protocol. SSP enables communication with other SAS devices. Each
PHY on the SAS adapter 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 adapter 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
logical 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.
T, U, V
virtual drive
A storage unit created by a RAID controller from one or more drives. Although a virtual
drive may be created from several drives, it is seen by the operating system as a single drive.
Depending on the RAID level used, the virtual drive can retain redundant data in case of a
drive failure.
W, X, Y, Z
52
Sun Storage 6 Gb SAS ExpressModule HBA • December 2014
Advertisement
Table of Contents
