Areca 24/4 Internal/External Port Pcie 3.0 12 Gb/s SAS/SATA Raid Controller 2Gb Cache - Manual (Page 160)

WEB BROWSER-BASED CONFIGURATION
160
• Tagged Command Queuing
The “Enabled” option is useful for enhancing overall system
performance under multi-tasking operating systems. The
Command Tag (Drive Channel) function controls the SAS
command tag queuing support for each drive channel. This
function should normally remain “Enabled”. “Disabled” this
function only when using SAS drives that do not support
command tag queuing. Tagged Command Queuing (TCQ) is a
technology built into SAS hard drives. It allows the RAID
controller to send multiple read and write requests to a hard
drive. This function should normally remain “Enabled”. “Dis-
abled” this function only when using SAS drives that do not
support command tag queuing.
• SCSI Channel/SCSI ID/SCSI Lun
SCSI Channel: The SAS RAID controller function is simulated
as a external SCSI RAID controller. The host bus is represent-
ed as a SCSI channel. Choose the SCSI Channel.
SCSI ID: Each SCSI device attached to the SCSI card, as well
as the card itself, must be assigned a unique SCSI ID number.
A SCSI channel can connect up to 15 devices. The SAS RAID
controller is a large SCSI device. Assign an ID from a list of
SCSI IDs.
SCSI LUN: Each SCSI ID can support up to 8 LUNs. Most
SAS controllers treat each LUN like a SAS disk.