Through its HDD Reimagine event, Western Digital has presented new storage units, which it has dubbed OptiNAND and consist of the integration in a single device of hard drives and SSD units. Which is not new, since that has already been done in the past with SSHD drives.
The advantage of these types of drives is that they combine the storage capacity of conventional hard drives with the transfer speed and seek time advantages of all NAND Flash-based memory. So in theory it brings together the best of both worlds in one device.
What is Western Digital’s OptiNAND technology?
Future Western Digital hard drives will integrate 162-layer 3D NAND Flash memory into the circuitry that accompanies the hardware controller of their new hard drives. Specifically, they have integrated their UFS memory technology, so they are not NVMe chips. This is not a limitation or a bottleneck in performance since UFS memories are several times faster in transmission speed than a conventional hard disk.
And what is it that differentiates OptiNAND technology from a conventional SSDH? The fact that in OptiNAND the Flash memory does not store complete data when copying the data, since just store the metadata that uses the hard disk internally to be able to perform certain operations faster and more reliably. Hard drives usually come with a microcontroller with RAM memory that performs these operations. But being conventional RAM memory this information is eliminated as soon as the hard disk has been turned off.
The fact that the hard disk has a large capacity of built-in NAND memory also means the increased communication speedas this allows you to send more data from the internal DRAM of the hard drive to the Flash memory built into these hard drives. This is achieved because the drive can use more rotational energy to send more data.
On which hard drives will it be implemented?
The first units to use OptiNAND technology will be non-SMR hard drives with 20 TB capacity, which unfortunately we will not be able to buy, at least for a while, as Western Digital has stated that they are going to sell them first to a number of previously selected key customers.
The 20 TB hard drives with OptiNAND technology from WD will consist of 9 plates and will continue to make use of technology energy-enhaced PMR or ePMR. From WD they affirm that OptiNAND technology is key to achieving the capacity of 2.2 TB per plate. Western Digital has plans to reach 50 TB of storage for its hard drives with OptiNAND technology.