Installation guide

Appendix B. Fibre Operation
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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 default 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 "Empty HDD Slot LED" function default setting is “ON”
Each slot has a power (Link/Access) LED to identify the HDD installed.
When there is no HDD installed. The power (Link/Access) LED will turn "OFF".
CPU Fan Detection
The "CPU Fan Detection" function is for RAID card only.
SES2 Support
If your SAS backplane does not implement the correct SES2 function, you can
disable the SES2 support on controller. Controller will use SMP (only monitor
PHY not environment) to communicate with SAS backplane, but you will not be
able to monitor the backplane information.