Stefan Mileschin

As operators of cloud datacenters need more storage capacity, higher capacity HDDs are being developed. As data hoarders need more capacity, higher capacity HDDs are needed. Last week Western Digital introduced its new Utrastar DC HC650 20 TB drives - hitting a new barrier in rotating data.

The drives feature shingled magnetic recording (SMR) technology, which layers data on top of another much like a shingled roof, and therefore is designed primarily for write once read many (WORM) applications (e.g., content delivery services). Western Digital’s SMR hard drives are host managed, so they will be available only to customers with appropriate software.

Western Digital’s Utrastar DC HC650 20 TB is based on the company’s all-new nine-platter helium-sealed enterprise-class platform, a first for the company. The new 3.5-inch hard drives feature a 7200 RPM spindle speed and will be available with a SATA 6 Gbps or SAS 12 Gbps interface depending on the SKU. Since the product is not expected to be available immediately, the manufacturer does not disclose all of its specifications just yet, but has stated that key customers are already in the loop.

Featuring a very high per-platter capacity of around 2.2 GB, the Utrastar DC HC650 20 TB HDDs offer a higher sequential read performance than its predecessors, but its IOPS per TB performance is lower than that of older HDDs. That said, Western Digital’s clients who will use the 20 TB SMR HDDs will need to manage the physical limitations of SMR, by maximizing sequential writes.

As far as availability is concerned, the 20 TB version of the Ultrastar DC HC650 SMR drives will be available as samples by the end of the year. Actual shipments will start once the drives are qualified by customers. Because the HDDs will be available to select customers only, Western Digital does not publish per-unit pricing.

https://www.anandtech.com/show/14861...or-datacenters