Stefan Mileschin

Western Digital has introduced its new series of SSDs designed for mission critical applications, including OLTP, OLAP, hyper converged infrastructure (HCI), as well as software-defined storage (SDS) workloads. The Ultrastar DC SS540 drives are aimed at mixed and write intensive workloads and can be configured accordingly. Since the SSDs use an SAS 12 Gbps interface, they are drop in compatible with existing machines.

The Western Digital Ultrastar DC SS540 is based on the company's sixth-generation dual-port SAS 12 Gbps platform co-developed with Intel as well as 96-layer 3D TLC NAND memory (presumably, also from Intel) and comes in a 2.5-inch/15 mm form-factor. The new SSDs are drop-in compatible with existing servers that support 9, 11, and 14 W per drive power options (SKUs with higher power consumption offer higher random read/write speeds).

As is traditional for SAS SSDs from Western Digital and Intel, the Ultrastar DC SS540 supports extended error correction code (ECC with a 1x10^-17 bit error rate) to ensure high performance and data integrity, exclusive-OR (XOR) parity in case a whole NAND die fails, and parity-checked internal data paths. In addition, the Ultrastar SS540 complies with the T10 Data Integrity Field (DIF) standard, which requires all interconnect buses to have parity protection (on the system level), as well as a special power loss data management feature that does not use supercapacitors. As usual, Western Digital's Ultrastar SS540 will be available in different SKUs with capabilities like instant secure erase and/or TCG+FIPS encryption to conform with various security requirements.

The manufacturer plans to offer the Ultrastar DC SS540 rated for 1 or 3 drive writes per day (DWPD) to target different workloads. The former will offer capacities between 960 GB and 15.36 TB, whereas the latter will feature capacities from 800 GB to 6.4 TB. The new lineup does not include drives rated for 10 DWPD and less than 1 DWPD, so those who need higher or lower endurance (as they run extremely read intensive or extremely write intensive workloads) will have to use previous-generation offerings from Western Digital. When it comes to warranty and MTBF, the drives are rated for a 0.35% annual failure rate (AFR), 2.5 million hours MTBF and are covered with a five-year limited warranty (or the max PB written, whichever occurs first).

https://www.anandtech.com/show/15066...b-up-to-3-dwpd