An Editorial Perspective 

The buzz in the industry these days in “green IT” and everyone who is anyone is going along for the ride. While there is nothing wrong with improving the manufacturing of disk arrays and other tech components to exclude nasty chemical compounds that play havoc with the Earth’s ecosystem, much of the greening of storage itself as touted by the vendor community is more marketecture than architecture.

Getting to green storage involves, depending on the vendor you consult, one or more of the following:

• Option 1: Change out disk drives for more capacious units that use the same amount of electricity. One leading enterprise storage vendor, EMC Corporation, has just announced its embrace of big SATA drives and its press releases are filled with information about how much more capacity a user will get from the same amount of power. In truth, they are re-treading the same turf already visited by competitor Network Appliance earlier in 2007. Now, every vendor of RAID arrays seems to be towing the line.
• Option 2: Add "thin provisioning" to get more efficient use of the disk capacity you have. Though pioneered by DataCore Software back in the 1990s, the term "thin provisioning" has been coined by 3PAR and other vendors to describe a kind of shell game that on-array software plays with “reserved but not yet allocated” disk space. Thin provisioning provides the customer with "more space" for storing data and this, so the story goes, is green because it enables the customer to defer additional purchases of storage arrays for awhile longer.
• Option 3: Deploy Massive Arrays of Independent Disk (MAID arrays), whose primary evangelist and vendor, COPAN Systems, has enabled technology to power down disk drives when they are not in use. Doing so, says the vendor, yields reductions in overall energy consumption by hungry disk spindles.
• Option 4: De-duplicate your data using products from companies like Data Domain or Diligent Technologies. Approaches vary somewhat, but basically you compress data by substituting a stub for a predefined bit pattern, which after several passes, makes big files smaller and frees up space for reuse on your disk drive. Like thin provisioning, this technology is said to be green because it enables the purchase of additional arrays to be deferred.
• Option 5: Use 1 through 4 in combination to see interesting capacity improvements that yield corresponding power demand reductions.

At first blush, any or all of the above “strategies,” while they might reduce power consumption rates in the short term, are not strategic at all. They do nothing whatsoever to address the root cause of the carbon footprint problem in IT -- the politically correct and “eco-conscious” way of saying increasing demand for electricity.

The root cause of accelerating power requirements for storage technology is the data itself – or, rather, it is unsorted and unmanaged “junk drawers” of data that we charmingly refer to as storage infrastructure. That storage arrays are quickly filling to the brim is less a sign of a sudden increase in business-relevant data, than a clear indication of mismanaged data.  We have gotten into the habit of storing all data, from the gems to the junk, in a huge undifferentiated mess that eats at storage capacity capacity the way that acid reflux syndrome eats the esophageal lining.

To address the root cause of climbing power demands strategically, we first need to “green” our data – parse through the data we store, save the stuff worth saving, then delete the rest. As Mike Linett, CEO of Zerowait, a high availability storage engineering firm, likes to say, “The delete key is the greenest key on the computer keyboard.”

That’s part of it. Green data is realized, in part, by culling out duplicate files, junk data, spam, contraband files, and orphan data from your storage repository.

A "deeper shade" of green is realized when you deploy an honest-to-goodness archive strategy at your firm, moving data that must be retained for business or regulatory reasons, but that has little chance of re-reference, onto green (low power) media -- like tape and optical.

Greening your data is strategic and capable of delivering long term power demand reductions. Greening your storage is tactical, and is ultimately about as beneficial as re-arranging deck chairs on the Titanic.

-- The Editor