Destroying hard drives, what a waste

Many financial and government organisations choose to destroy the hard drives that are declared as failing and removed from their arrays. They use products like this which make the hard drive unusable.

What happens to these hard drives? I presume they just end up in landfill and aren't recycled. Is it beyond the wit of man to find another solution?

First of all, a large number of these drives haven't actually failed. They've been marked as having a potential to fail by the array and before a hard failure occurs, the data is moved off to a hot spare. Naturally it is more efficient to copy parity generated data like RAID-5/6 to another drive than to read all drives in the parity group and rebuild the data.

Second, we are imbedding encryption directly into the drive itself. Can't we simply create a drive where the keys can be wiped in the event that the drive needs to be recycled? This seems to me to be the simplest and most elegant solution.

Incidentally, I checked the Hitachi Global Storage Technologies (HGST) website and could only see some nice words about caring about the environment but nothing specific relating to recycling itself.

2.5" Enterprise Arrays

I was asked the question today, when will Enterprise arrays support 2.5" drives as standard? It's a good question, as at first glance the savings should be obvious; smaller, lower power drives, more drives in an array and so on.

However things aren't that simple. Doing the comparisons and working out some of the basic calculations such as Watts per GB or GB per cm3 then 2.5" drives don't offer that much of a saving (if at all). I've posted some sample comparisons here.

I'm not aware of any vendors who are planning to offer 2.5" drives in Enterprise arrays. Looking at the mechanics of making the conversion, then there would be a few issues; first is the interconnect, SAS versus FCAL, however that should be an easy one to resolve. Second, there's the physical layout of the drives and prividing maintenance access to each of them. That might prove more tricky, achieving a high density footprint and providing access to each drive individually.

If anyone is aware of anyone planning to use 2.5" drives as standard, please let me know.

The Case of Decimal v. Binary

We all know that disk drive manufacturers have been conning us for years with their definition of what constitutes a gigabyte. There are two schools of thought; the binary GB, which is 1024x1024x1024 or 1,073,741,824 bytes and the decimal GB which is quoted as 1000x1000x1000 or 1 billion bytes. The difference is significant (7.4%) and something that has annoyed me for years, mainly for having to explain to "management" why the 100TB of storage they bought stores less than 100TB of data (significantly less with some manufacturers).

Seagate have just lost a class action law suit (see here) which means they are forced to give a 5% rebate to customers plus some free backup software.

Unfortunately, those of us who have purchased storage subsystems from vendors will not be able to claim as the case refers to customers who bought stand-alone units:

"You are a member of the settlement class if, between March 22, 2001 and September 26, 2007, you purchased in the United States a new Seagate brand hard disc drive from an authorized Seagate retailer or distributor, separately as a Seagate product that was not pre-installed into and bundled with a personal computer or other electronic device."

So I guess EMC/HDS/IBM can breathe easy at this stage. It does beg the question though, when are our large array vendors going to quote the real figures for the usable storage available on an array? I have various calculators I use to help me work out the usable storage (before and after LUN creation and with varying RAID types) as I need to present real rather than throretical figures when sizing arrays. I think we need some more transparency here.

Disk Sizes Continue to Dazzle

HGST (Hitachi Global Storage Technologies) announced yesterday that they have managed to further miniaturise the drive heads they use in the hard disk drives. I hadn't realised exactly how small these recording heads were; apparently 2000 times smaller than the width of a human hair. Called "current perpendicular-to-the-plane giant magnetoresistive1 (CPP-GMR) heads" (I copied that from the press release to save me getting it wrong) which is a snappy title for any technology, these new heads will apparently move us closer to 4TB drives.

As I previously posted, hard drive technology these days is just amazing. All I can say, is keep it up guys!

Your Data on a Knife Edge

I read this interesting article on the BBC website today. It talks about how two European scientists (Albert Fert and Peter Grunberg) have won the Nobel prize for physics for GMR (giant magnetoresistance). This technology has enabled hard drives to be made smaller and to hold more data. What I liked most was the following comment, used to describe the technology:

"A computer hard-disk reader that uses a GMR sensor is equivalent to a jet flying at a speed of 30,000 kmph, at a height of just one metre above the ground, and yet being able to see and catalogue every single blade of grass it passes over."

What a great description of the (extremely cheap) technology we simply rely on every day to provide us our data. With those kinds of tolerance levels, our information really is on a knife edge.

So next time, you moan about a disk failure, just imagine being on that jet...

Tower of Tera

Lots of talk today about the 1 terabyte drive from Hitachi. In fact the drive is more likely to be about 931GB based on the dubious practice of using decimal 1000's rather than binary (whilst we're on that subject, the concept of decimal versus binary does annoy me - what with that and overhead, on some of the AMS's I've installed, a 300GB drive comes out as 267GB).

So, yes, I want a 1TB drive - no idea what I want to put on it, or how I'll back it up - but I want one.

Hybrid Storage Alliance

Fujitsu, Hitachi, Toshiba, Samsung and Seagate are getting together as the Hybrid Storage Alliance to promote the use of HDDs with large amounts of additional cache. They've set up a (not so snazzy) website at www.hybridstorage.org (check out the builder on the features page - when did you last see a builder using a laptop, never mind understanding what a hard disk is).

It's good news. I love the idea and have mentioned my thoughts before. I also think that onboard cache provides more options to develop the successor to RAID, although I'm still thinking how it could be done.

Sandisk also announced the device shown on the right - a solid state HDD. After 50 years, the hard disk is seeing some exciting changes.

Full details of the Sandisk announcement at http://www.sandisk.com/Corporate/PressRoom/PressReleases/PressRelease.aspx?ID=3654.