WD has come up with an integrated NAND and hard disk called OptiNAND which used technology from both divisions. WD has found a way to extend extended PMR technology to 20TB without using shingling. Write operations are recorded to reduce adjacent track interference. A sample 20TB OptiNAND drive is shipping, and WD says OptiNAND will be used in all its disk drives in the future.
OptiNAND which includes an iNAND universal flash storage (UFS) embedded flash drive (EFD). Not a hybrid technology, but a smarter, faster, denser storage drive that could reach an estimated 50TB of capacity this decade.
The runaway train that is data proliferation shows no signs of slowing. More than twice the amount of data will be created in the next five years than has been created since the advent of digital storage. New sources such as AI/ML, blockchain, sensors, 5G networks, connected automobiles and more are driving this growth—and with it, a rapidly increasing need for robust, reliable storage. Our customers are relying on Western Digital to help them meet this need.
Western Digital’s technological expertise and leadership, together with a diverse portfolio of high performance HDD and flash products, make us uniquely positioned to help customers meet this demand at scale.
Though it’s more complex than it sounds, in HDDs, the straightforward way to add more storage is to add more storage disks and more write heads. But doing so is not necessarily the most cost-effective way. Helium disks have been on the market for several years but they cost more per GB than conventional disks.
By enabling write-cache, the drive can be a little more dynamic with its operations, because it can schedule writes and reads (and refreshes) in the most efficient order possible. Thus, performance will be faster. But there is that slim chance that, in a sudden power loss, the drive never actually has the chance to write the data to disk.
But with OptiNAND, the data will be saved to non-volatile NAND memory to prevent data loss. This can save systems from data loss when the power fails.
The density improvement is surely needed as 18TB disks are taking up a spectacular amount of space. Seagate is undoubtedly looking at WD’s approach while Toshiba is also working in their designs. Adding flash NAND to hard disks may well be the direction of the industry looking forward. The improvement is track stability may allow for even larger amounts of data on a given platter.
WD, Seagate and Toshiba have long studied ways to increase the number of tracks per inch the platters. The denser the tracks the higher the cross talk between adjacent tracks. So called perpedicular recording is simply tighter magnentic regions on the hard disk. A carbon overcoat can be changed to graphene which may solve some density problems. As much as 5Tb/in2 aerial density may be possible with codevelopment of HAMR techniques.
It may be a few months down the road before these disks are widely available. WD probably will sell many disks to coporate servers before they are available more widely. While incremental in capacity, the new capacity is welcome for many server users. Toshiba and Seagate are still popular with consumers and now that WD has a new model many NAS users will buy a lot of them.