Installation guide

Chapter 5. McBIOS Configuration
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5.5.5.8 Volume Data Read Ahead
The 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 know the
application behavior. 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.
5.5.5.9 Hdd Queue Depth Setting
This parameter is adjusted the queue depth capacity of NCQ (SAS HDD) or
Tagged Command Queuing (SAS HDD) which transmits multiple commands to
a single target without waiting for the initial command to complete.
5.5.5.10 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 RAID controller will light the fault LED; if no HDD
installed.
5.5.5.11 Controller Fan Detection
The "CPU Fan Detection" function is for RAID card only. (Default: Disabled)
5.5.5.12 Auto Activate Raid Set
When some of the disk drives are removed in power off state or boot up stage,
the RAID set state will change to “Incomplete State”. But if a user wants to
automatically continue to work while the RAID controller is powered on, then
user can set the “Auto Activate Raid Set” option to “Enabled”. The RAID state
will change to “Degraded Mode” while it powers on.
5.5.5.13 Disk Write Cache Mode
User can set the “Disk Write Cache Mode” to Auto, Enabled, or Disabled.
“Enabled” increases speed, “Disabled” increases reliability.