Areca ARC-5030 Series, Руководство пользователя

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WEB BROWSER-BASED CONFIGURATION
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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 perfor-
mance under most circumstances.
• Stagger Power on
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 subsystem. 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
designed to meet short-term startup power demand as well as
steady state conditions.
300MB/s. NCQ is a command protocol in Serial ATA that can
only be implemented on native Serial ATA hard drives. It al-
lows 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 RAID
subsystem allows user to choose the SATA Mode: SATA150,
NCQ, SAT300, NCQ.