Helium-Filled Hard Drives, Steering Paradigm Shift in Storage
Processing over billions of streaming minutes per month to over 48 million viewers, Netflix, a provider of video stream service, was concerned on its energy budget which was spent merely on storing content on tens of thousands of hard drives and supplying power for the cooling fans to keep those drives from heating up. They were seeking to acquire a reliable storage media to accommodate the unprecedented data growth of their video streaming service that could store more data and save power consumption. Even, engineers and directors are working hard to compensate performance, capacity, and the size of storage media for their organization.
Worldwide, most of the enterprises use HDDs as their storage media because of its low cost implementation and high storage capacity than other devices such as SDDs and USBs. HDDs use platters, which are covered with magnetic materials to store data. Unlike the spin of magnetic head and tape in cassette players while retrieving data, hard disk’s head and platter cannot contact each other due to the rotational speed of about 15,000 rotations per minute (rpm). This tremendous speed leads to damage both head and platters if they collide. Air as a lubricant controls this friction between the moving parts. Air supports each mount—one platter with read and write heads— with higher number of rotations per minute to read and write data. However, we know that Air is the mixture of gases. Its density changes as it holds heat and moisture which causes friction with the moving parts. This restricts the usual Air-filled HDDs to a maximum of five spinning platters which on the contrary could have actually held more platters and store more data.
To overcome this hindrance, Helium can be used in place of Air. Comparing the theory of Helium and Air, let us look at the efficiencies of each of them: Helium is much less dense than Air and provides less resistance and turbulence, allows more platters, yet consumes less power than the normal HDD. Replacing Air with Helium, produces less Air turbulence, which in turn saves power consumption, produces less heat, fewer vibrations, makes less noise, allows greater drive capacity, and results in a much lower total cost of operation.
For over a decade, storage industry, particularly the HDD companies such as Seagate, Western Digital, and IBM have constituted ways to bring the helium filled hard drives into reality. In the hunt to leverage the benefits of Helium within their storage appliances, Hitachi Global Storage Technologies (HGST), a subsidiary of Western Digital, invented and formulated a hard drive to increase storage capacity, reduce heat and cost, and all other factors that block the performance of the device. They have built a way to reliably seal Helium gas inside a hard drive that would compensate all the requirements to the better performance of the HDDs. With the help of HGST, Western Digital has developed the computer hard drive sealed in a Helium atmosphere leveraging HelioSeal Technology. HelioSeal technology helps in hermetically sealing Helium inside the drive. The drive was designed for users particularly in data centers where hundreds and thousands of computers are operated. Seagate, on the other hand, had also developed hermetic helium-filled HDDs with a rugged cover weld design capable to avoid damage of the drive in any conditions.
Netflix acquired Helium HDDs from Western Digital and run a pilot session in to their service. The result showed 50 percent capacity gain while cutting down energy needed by 23 percent. In addition, Netflix was able to reduce cooling costs and are 4–5°C cooler than traditional Air-filled HDDs. David Fullagar, Director of CDA, Netflix says that the company is saving about 90 watts per appliance. He points that this savings is way more significant when considering thousands of streaming appliances.
Available Products of Helium HDDs
Though the drives are expensive to manufacture, the cost is recovered in energy savings and performance gains. Western Digital and Seagate are Manufacturing Enterprise Capacity Helium HDDs ranging from 8TB to 10TB. All the Helium HDDs are same as the size of Air-filled HDDs—3.5 inch, yet save more data and energy. These companies release HDDs with various specs and features including model, encryption, capacity, interfaces such as SAS and SATA.
Western Digital has two products of Helium HDDS: Ultrastar He10 and Ultrastar He8. Both Ultrastar He10 and He8 are 3.5-inch in width and have variants of 10TB & 8TB and 8TB & 6TB respectively. Meanwhile, Seagate’s all Enterprise Capacity Helium HDDs have capacity of 10TB and come with different models and encryption standards according to the requirement. Further, Seagate plans to introduce 20TB Helium HDDs by 2020 reports Computer World.