A couple of weeks ago, I gave you the lowdown on solid state drives: what they're for, how they work, and where they're headed. In the name of equal time, I also got the scoop on the future of traditional hard drives, in case you were worried that your beloved, clackety drive of yore was going the way of the telegraph. Indeed, hard drives aren't going anywhere: in fact, they're just getting bigger and better, and more high tech by turns.
To tell us all about the future of the HDD, I grilled Sherman Black of Seagate [NYSE:STX], whose stolid performance under my ruthless* questioning led me to believe that the fate of HDDs is quite promising. I first positited to him the notion that I've heard grumbled by more than a few IT guys: that as notebook drives get bigger, they also fail more easily.
"20 years ago, people were saying the same thing about 5 megabyte drives," he said. In actuality, HDDs are getting increasingly reliable and long-lived, and according to Black, R&D dollars are still being spent deriving new technologies for capacity and reliability. Unforunately, that means we won't see a staggering drop in gigabytes-per-dollar over the foreseeable future, but it does mean that we'll see some interesting developments in the way of power usage. "We're focused on power," Black says, especially when it comes to enterprise customers running big, hot storage centers. Lower power usage equals less heat for data centers, and less energy required of notebook batteries — good things all around.
But unlike solid state drives, which store their data on chips, HDDs must put a special premium on physical space; HDDs use stacks of disks to store data, which are read by arms and heads that skim over the surface of the disks (think of a record player reading an LP.) Of course, you can only fit so many disks inside a drive before they become to fragile or crowded to operate. To solve that problem, companies like Seagate are focussing on "aerial density," or the practice of squeezing more bits into the same recording area on a disk platter. The old method of storing data on a hard drive disk was called "longitudinal data writing," in which data was written sideways across the surface of a disk (much like a CD or DVD). New data writing technology allows the drive to write vertically, using the entire thickness of the disk, as well as its longitudinal surface, for greater density.
Seagate is also improving its signal-to-noise ratio, which before limited the speeds at which heads could read data off spinning disks. A better ratio means the ability to stack disks closer together, all of which are moving at up to 15,000 RPM. Pretty amazing feat of physical science, considering the delicacy of the parts involved. To make sure everything continues to work to par, despite extreme physical duress, Seagate is improving the motor bearings of its drives, as well as developing better "data management" firmware that will allow the drive to shut down as much of itself as possible when not in use.
All these impovements have culminated for Seagate in the announcement of the company's first 1.5TB drive, which of course, begs the question: who the hell needs 1.5TB drive? Black claims that's a question HDD companies are still feeling out: underestimate users' needs, and get caught underproviding, but overestimate it and you end up blowing R&D money on drives that are way too big.
So will SSDs eventually vanquish HDDs? Not anytime soon. More likely is that they'll work in tandem, as they are starting to in servers, with SSDs handling frequenly-accessed data and HDDs serving as a kind of vault for less used stuff. It's cool to imagine a notebook with a terabyte of cold storage and 100GB of solid state memory ready to whip out your email, docs, music and movies — but that's a few notebook generations down the road. Still, a nerd can dream.
*It was actually a rather pleasant conversation, during which I sipped tea.