News

posted on 04 March 2008 18:10

Xyratex has introduced spin-down capability with Advanced Power Management (APM) technology. It comes with the F5404E RAID controller and can save up to 40 percent in power dissipation by automatically spinning down disk drives.

Sysadms can create policies to identify disk drives that are not being accessed.The APM software uses these policies and 'identifies groups of physical drives that are accessed in parallel and spins down and spins up drive groups to satisfy requests from applications running on attached servers. A schedulable patrol function regularly evaluates drives that have been spun down to ensure they will spin up on demand without affecting applications' performance, availability or reliability.'

This is not MAID (Massive Array of Idle Disks) technology as first used by Copan and then implemented by Nexsan (AutoMAID). In that scheme the bulk of the disk drives in an array are spun down. This means the array generates much less heat and the drives can be packed very closely together. The packing density is way beyond what a Xyratex, Dot Hill or any other vendor can achieve, even with spin-down.

This suggests that a MAID array is best used for a long-term disk archive with no transactional IU/O component. But the Xyratex array can be used in mid-tier disk storage situations where fast transactional I/O performance is not characteristic of the the whole array and disks can be safely spun down (but not stopped) as applications and users that will access the data on them can tolerate the small increase in data access time that will inevitably result as they spin up to full speed again.

The APM software will initially be implemented on the 48-drive F5404E RAID system and incorporated throughout the remaining Xyratex RAID family by mid-2008.

EMC has said it will introduce spin-down capabilities to its drive arrays.

We can expect Xyratex' OEMs to gladly take up this technology and announce it in their own products. These are said to include NetApp, 3PAR, Compellent, Equallogic, LeftHand Networks and Rackable Systems,