Sans Digital ER208UT+B, Руководство пользователя

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LCD CONFIGURATION MENU
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Disable: No NCQ support
ESB2/MACPro/Siliconlimage: Intel ESB2, MACPro and
Siliconimage SATA controller
ICH: Intel ICH series SATA controller
Marvell6145: Marvell 6145 SATA controller
nVidia: Nvida SATA controller
3 .7.6.8 HDD Read Ahead Cache
Allow Read Ahead (Default: Enabled)—When Enabled, the drive’s
read ahead cache algorithm is used, providing maximum perfor-
mance under most circumstances.
3 .7.6.9 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 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.
3 .7.6.10 Stagger Power On Control
In a PC system with only one or two drives, the power can sup-
ply enough power to spin up both drives simultaneously. But in
systems with more than two drives, the startup current from
spinning up the drives all at once can overload the power sup-
ply, causing damage to the power supply, disk drives and other
system components. This damage can be avoided by allowing
the host to stagger the spin-up of the drives. New SATA drives
have support staggered spin-up capabilities to boost reliability.
Staggered spin-up is a very useful feature for managing multiple
disk drives in a storage controller. It gives the host the abil-
ity to spin up the disk drives sequentially or in groups, allowing
the drives to come ready at the optimum time without straining
the system power supply. Staggering drive spin-up in a multiple
drive environment also avoids the extra cost of a power supply