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Background Task Priority
•
The "Background Task Priority" is a relative indication of how much time the controller devotes to a
rebuild operation. The SAS RAID controller allows the user to choose the rebuild priority (UltraLow,
Low, Medium and High) to balance volume set access and rebuild tasks appropriately. For high array
per
formance, specify a "Low" value.
JBOD/RAID Configuration
•
JBOD is an acronym for "Just a Bunch Of Disk". A group of hard disks in a RAID box are not set up as
any type of RAID configuration. All drives are available to the operating system as an individual disk.
JBOD does not provide data redundancy. User needs to delete the RAID set, when you want to
change the option from the RAID to the JBOD function.
SATA NCQ Support
•
The controller supports both SAS and SATA disk drives. The SATA NCQ allows multiple commands to
be outstanding within a drive at the same time. Drives that support NCQ have an internal queue
where outstanding commands can be dynamically rescheduled or re-ordered, along with the
necessary tracking mechanisms for outstanding and completed portions of the workload. The SAS
RAID controller allows the user to select the SATA NCQ support: "Enabled" or "Disabled".
HDD Read Ahead Cache
•
Allow Read Ahead (Default: Enabled)—When Enabled, the drive's read ahead cache algorithm is
used, providing maximum performance under most circumstances.
Volume Data Read Ahead
•
The volume read data ahead parameter specifies the controller firmware algorithms which process
the Read Ahead data blocks from the disk. The read ahead parameter is normal by default. To
modify the value, you must set it from the command line using the Read Ahead option. The normal
option satisfies the performance requirements for a typical volume. The disabled value implies no
read ahead. The most efficient value for the controllers depends on your application. Aggressive
read ahead is optimal for sequential access but it degrades random access.
HDD Queue Depth
•
This parameter is adjusted the queue depth capacity of NCQ (SATA HDD) or Tagged Command
Queuing (SAS HDD) which transmits multiple commands to a single target without waiting for the
initial command to complete.
Empty HDD Slot LED
•
The firmware has added the "Empty HDD Slot LED" option to setup the fault LED light "ON "or "OFF"
when there is no HDD installed. When each slot has a power LED for the HDD installed identify, user
can set this option to "OFF". Choose option "ON", the SAS RAID controller will light the fault LED; if
no HDD installed.
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