Earlier this year, Western Digital made headlines with the launch of its Ultrastar DC SN861 SSDs. Initially, the company kept tight-lipped about the controller behind these drives, leading many to guess they were using a proprietary model. However, recent insights have revealed a twist—it turns out Western Digital opted for a controller from Fadu, a South Korean enterprise known for its high-grade SSD solutions, established back in 2015.
The target audience for the Western Digital Ultrastar DC SN861 SSD includes hyperscale datacenters and enterprise clients that are shifting towards PCIe Gen5 storage solutions. A dive into a Storage Review article recently unveiled that these drives rely on Fadu’s FC5161 NVMe 2.0-compliant controller. This powerhouse controller employs 16 NAND channels that work with the ONFi 5.0 2400 MT/s interface. It packs a punch with enterprise-level capabilities such as OCP Cloud Spec 2.0, SR-IOV, support for up to 512 namespaces for ZNS, flexible data management, NVMe-MI 1.2, and a raft of advanced features like security, telemetry, and power loss defense—capabilities that set it apart from previous Western Digital infrastructures.
In terms of performance, the Ultrastar DC SN861 SSDs don’t hold back. They deliver sequential read speeds reaching 13.7 GB/s, while sequential write speeds hit up to 7.5 GB/s. When it comes to handling random tasks, these drives showcase impressive numbers with up to 3.3 million random 4K read IOPS and up to 0.8 million 4K write IOPS. They come in a range of capacities, from 1.6 TB to 7.68 TB, and offer durability levels which support between one to three drive writes per day over the span of five years. Plus, you can pick between U.2 and E1.S form factors depending on your needs.
The two shape options—the SN861’s U.2 and E1.S—might share a technological backbone, but each has been honed for specific tasks. The E1.S model shines with features like FDP and enhancements that elevate performance in cloud setups. On the flip side, the U.2 version is crafted for robust enterprise uses and cutting-edge applications like AI innovations.
One cannot overlook the Ultrastar DC SN861’s eco-friendly stance with its modest 5W idle power consumption—a notable feat in the enterprise realm. This efficiency marks a 1W reduction compared to its predecessor, the SN840, a seemingly small change that can cause significant differences when scaled across data centers.
Right now, interested buyers, including tech giants like Meta, can get their hands on these SSDs, though pricing details are shrouded in mystery, hinging, as expected, on buying volumes.
Sources include insights from Fadu and a comprehensive breakdown courtesy of Storage Review.
