What is... MAMR?
We investigate a potential home for all of the Big Data we’re creating.
We have too much data, and the rise of connected sensors and Big Data means we need somewhere to store it all. Hard drives have shrunk in physical size and grown in storage capacity, but new technologies are needed to let those trends continue.
Western Digital’s answer is MAMR, using microwaves to make writing bits to the disk easier. It promises a 40TB drive by 2025, with a storage density of four terabits per square inch.
Haven’t I ready about MAMR in PC Pro before?
We interviewed Thomas Thomson, professor of nanotechnology, about microwave-assisted magnetic recording way back in issue 242 – on p126, if you still have your copy – and its predecessor/competitor, HAMR. Which we don’t need to tell you stands for heat-assisted magnetic recording.
How does it work?
Both HAMR and MAMR are energy-assisted recording technologies, which aim to boost density by making it easier to write on the disk, cramming more bits into the same amount of space. For more capacity in a 3.5in format, manufacturers can shrink the magnetic grains that store information. That also requires a tinier write head to flip each of those magnets into up or down position. But, overcoming the magnetic field to do that is tougher for the smaller write head, so it needs a helping hand.
Why is MAMR better than HAMR?
HAMR does this by heating up the media via a laser to lower the energy barrier to write, making those magnets flip more easily – but that introduces reliability issues and is expensive. All those tiny lasers don’t come cheap. MAMR makes it easier to write to the disk by creating an electromagnetic field, thanks to a widget in the head called a spin torque oscillator. That adds a boost like HAMR’s heat, but without the reliability issues caused by the higher temperatures.
Why are we only doing this now?
Both HAMR and MAMR have been theoretical ideas in the pipeline for decades, but the problem has been building a tiny write head that can create the MAMR environment. That’s what Western Digital has achieved.
And that means bigger hard drives?
Western Digital is promising 40TB drives by 2025, and even larger in the years to follow, and it’s likely that rival hard drive makers will follow suit with their own versions, too. Toshiba and TDK are also researching the idea.
Why not just use solid state?
Seagate last year unveiled a 60TB SSD, a whopper that far outstrips Samsung’s rival with a piddling 15TB capacity. While technically impressive, they’re financially problematic: reports suggest Seagate’s will cost upwards of $20,000. Plus, it still hasn’t been released. Western Digital didn’t reveal prices for its MAMR disks, but claimed the cost per terabyte would be in line with existing hard drive technologies – keeping them cheaper than SSDs, for now. While that gap is narrowing as SSD technology advances, MAMR could become the budget choice for enterprises.
What about those of us not building data centres?
Western Digital plans to have MAMR drives shipping to consumers, not only data centres. The push to 8K video might drive more home storage needs, though most of us don’t need dozens of terabytes at the moment and there are plenty of multi-terabyte drives already on the market. Of course, MAMR might not just expand home storage, but also further drive down prices.