Earlier this year, Western Digital took the wraps off its Ultrastar DC SN861 SSDs. However, the company kept mum about the controller used in these drives, leading many to speculate that WD relied on their own controller. A recent deep dive into the drive’s hardware revealed a different story; the controller actually hails from Fadu, a South Korean player in the enterprise SSD arena established in 2015.
This Ultrastar DC SN861 SSD caters to the demanding needs of hyperscale datacenters and other enterprise clients transitioning to PCIe Gen5 storage. Highlighted in a Storage Review piece, the drive features Fadu’s FC5161 NVMe 2.0-compliant controller at its core. This controller wields 16 NAND channels, works with an ONFi 5.0 2400 MT/s interface, and provides a suite of enterprise-specific features. These include the OCP Cloud Spec 2.0, SR-IOV, the ability to support up to 512 namespaces for ZNS, flexible data management, NVMe-MI 1.2, bolstered security measures, telemetry, and crucial power loss protection—capabilities that had not been seen in previous Western Digital controllers.
Performance-wise, the Ultrastar DC SN861 doesn’t disappoint. It offers impressive sequential read speeds hitting 13.7 GB/s and can write sequentially at up to 7.5 GB/s. When it comes to random data handling, it can achieve up to 3.3 million 4K random read IOPS and up to 0.8 million 4K random write IOPS. Buyers have choices between capacities ranging from 1.6 TB up to a hearty 7.68 TB, available in configurations supporting either one or three drive writes per day (DWPD) over a five-year span. Moreover, the SSD is available in both U.2 and E1.S form factors.
These two form factors are not just different in shape; WD has fine-tuned them for specific work scenarios. The E1.S variant steps up with FDP and cloud-centric performance tweaks, while the U.2 model is better suited to handle intense enterprise applications, like those in AI.
What’s also noteworthy about the Ultrastar DC SN861 is its power efficiency. With idle power usage clocking in at 5W, it’s notably thrifty compared to the usual enterprise-grade SSDs, including being 1W more efficient than its predecessor, the SN840. For companies dealing with thousands of drives, like hyperscalers, every watt of saved power helps reduce total cost of ownership significantly.
Currently, the Ultrastar DC SN861 SSDs have hit the market, primarily accessible to select clients, including names like Meta, and those keen on these high-performance drives. The pricing is still under wraps and likely varies depending on ordering volumes and customer agreements.
Sources reveal deep insights into this drive’s capabilities and showcase its potential, underscoring Western Digital’s commitment to cutting-edge storage solutions.
