Consistent capacity growth in hard disk drives (HDDs) has become something we take for granted. It isn’t so trivial if you think about the fact that there are in fact physical limits to how much data you can store on one disk and every now and then we are nearing a limit that can’t be topped anymore. The last limit was hit in 2005 and the next seems to be arriving in the 2013 – 2015 timeframe. However, a new technology breathes new life into HDDs. HAMR will bring massive storage growth and propel the industry far beyond 100 TB.
When Samsung announced its new 2 TB Spinpoint HDD last week and mentioned that it can now store 667 GB on one 3.5-inch disk, I remembered how far the current perpendicular recording technology has come since its launch in 2006. The first 3.5-inch PMR drive, Seagate’s Cheetah 15K.5, packed only 75 GB on one disk. Back then, the storage density of PMR disks was just over 100 GB/inch2 and the industry forecasted that PMR will reach about 1 TB/inch2 until it runs out of room.
It was a natural question to ask where the current Spinpoint drive stands. It turns out that it is over 700 Gb/inch2 already, while Seagate’s mass market drives have reached 541 Gb/inch2. At the current pace, it appears that the industry will run out of room in the not too distant future. So I called up Seagate to find out more.
Seagate SVP Mark Re told me that Seagate in fact believes that there will be just a few more PMR product generations and a new technology will be necessary within 3 to 5 years as PMR may reach its end just north of 1 Tb/inch2. Re said that the industry has a choice to transition to patterned media or heat-assisted magnetic recording (HAMR) to decrease the distance between bits on the disk and increase the maximum areal density. Re declined to pinpoint the potential of HAMR exactly, but said that Seagate currently expects a soft limit to arrive at about 50 Tb/inch2. If the 3.5” HDD form factor survives, then we should see PMR to top out at about 5-6 TB per drive. With roughly 50x the potential of PMR, HAMR should lead the way beyond 100 TB drives and possibly into the region of 200 – 300 TB in the 2020 to 2025 time frame.
Given the fact that the first HDD stored 4.4 MB on 50 24-inch disks, this is a truly stunning prospect. Imagine the storage capabilities of a 100 TB drive. 250,000,000 average MP3 songs or 250,000,000 12 MP photographs. Or 2000 completely filled Blu-ray discs or hundreds of 3D movies. While data volumes of content will continue to evolve, HDD capacity will evolve as well and it is reasonable to expect that single HDDs will be able to store the digital lives of multiple generations of a family. And even if the end of HAMR is reached, Seagate expects HDD technology to continue to evolve. Beyond HAMR, Seagate believes that patterned media will emerge and enable further capacity increases. If the current trend continues, then we should HDDs to remain with us as an affordable mass storage technology well beyond 2025. Flash will not be able to touch the value proposition HDDs in terms of price, capacity and performance, Re said.
According to the executive, Seagate has built HAMR prototype drives already, but the technology is not yet at a point where it could be commercialized. In fact, while HAMR is derived from a technology called “optical assisted magnetic recording” that was developed by Quinta, a company Seagate acquired in 1998, HAMR is a much more evolutionary approach. In contrast to Quinta’s optical read/write head, HAMR will use a traditional read/write head. The change to current HDD technology will be somewhat moderate, but also require companies to change the surface coating of the disks. Instead of a cobalt material, HAMR will use iron-platinum.
What will remain the same is the reliability of HDDs. Despite the massive increase of storage capacity that may be frightening to some users, given the amount of data that could be lost, Re said that there will be no major changes from today’s technology. The company will continue to drive reliability innovation through software and make backups easier.
