Proware EP-4643S2D2-F8S6, User Manual

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Fibre to SAS/SATA Disk Array
User Manual 121
5.5.3 HDD Power Management
MAID (
M assive A rray of I dle D isks) is a storage technology that employs a large group
of disk drives in which only those drives in active use are spinning at any given time.
This reduces power consumption and prolongs the lives of the drives.
MAID is designed for Write Once, Read Occasionally (WORO) applications such as Data
Backup, Document, Mail server, and so on.
MAID technology focuses on "Green Storage Concept" to save power consumption and
enhance disk drives effective usage, i.e., "disk drives are spun down when there is no
activity or I/O on the drives".
In the Disk Array, MAID is implemented in the
HDD Power Management menu. Using
the Advanced Power Management (APM) function of disk drives, HDD Power
Management has three options (MAID Levels): (Level 1) Place idle drives in Lower Power
Mode, where the drives’ heads are unloaded; (Level 2) Place idle drives in Low RPM
Mode, where drives’ heads are unloaded and slows down to around 4000 RPM; and
(Level 3) Spin down idle drives, where drives stops spinning and goes into sleep mode.
Stagger Power On Control:
This option allows the Disk Array’s power supply to power up in succession each
HDD in the Disk Array. In the past, all the HDDs on the Disk Array are powered up
altogether at the same time. This function allows the power transfer time (lag
time) from the last HDD to the next one be set within the range of 0.4 to 6.0 seconds.
Default is 0.7 seconds.
Time to HDD Low Power Idle: (MAID Level 1)
This option enables the Disk Array to place idle HDDs of a Raid Set in Low Power
Mode, where drives’ heads are unloaded. The power consumption of the Idle HDD
saving is around 15% to 20%. Recovery time is under a second.
Options are: Disabled, 2, 3, 4, 5, 6, and 7 (Minutes).