News

posted on 16 July 2008 08:12

---

IBM has added MAID functionality to its non-mainstream DCS9550 disk drive storage product.

You'll loook in vain for the DCS9550 on the disk storage product pages on www.ibm.com, for example here, where it is not mentioned at all. What is it? The product has been identified as drive storage used in IBM's SOFS (Scale Out File Services offering) a bundle of products.

Here is what IBM's May 22, 2007, hardware announcement says about it: 'The IBM System Storage DCS9550 Storage System, consisting of the IBM System Storage DCS9550 controller and companion IBM System Storage DCS9550 Storage Expansion Units, is designed to address the storage needs of highly scalable data streaming applications. These applications run on Deep Computing systems, System p HPC systems, and System x e1350 Linux Cluster systems. The DCS9550 Fibre Channel (FC) controller Model CP1 attaches to the DCS9550 Storage Expansion Units, which are available in FC disk and SATA disk models, and scale up to 320 disks, giving you up to 160 TB of physical storage capacity with a single controller.'

In August, 2007, IBM expanded  the product to offer 960 drives and 720TB. It had added 750GB SATA drives.

The price in May was $240,000 for the main controller with extra for disk drives, a 500GB SATA drive priced at $1,100. In August 2007 a 750GB SATA drive was $1532. With 1TB drives available today the DCS9550 capacity could theoretically go up another 25 percent to 900TB. However IBM has made no announcement about this.

IBM says 'DCS9550 Sleep Mode option enables Massive Array of Idle Disks (MAID) capability. This feature is designed to put "idle" tiers of SATA disk drives into standby mode to reduce power consumption and save energy. ... In standby mode, the mechanical head assembly is parked within the disk drive, and the spindle is stopped,saving energy and helping to reduce power consumption within the datacenter.'

MAID was invented by Copan and similar functionality is being added to other suppliers nearline drive arrays as power-down or spindown.

IBM has not added MAID to its mainstream drive arrays, the DS3000, DS6000 or DS8000.

How the DCS9550 relates to IBM's scale-out XIV technology is not clear.

^{[Chris Mellor.]}