NVMe ZNS Makes It Into Linux 5.9 Along With MD RAID Fixes

NVMe 2.0's Zoned Namespaces (ZNS) functionality is now supported by the mainline Linux kernel.

NVMe ZNS is similar to Shingled Magnetic Recording (SMR) and Zoned Block Commands (ZBC) for allowing application/software control over the placement of data. With NVMe ZNS, it's over the placement of data obviously on NVMe SSDs within zones, allowing greater control to the OS rather than just the NVMe device for deciding on data placement. The goal of these technologies is to increase drive lifetime, ideally offer lower latency and greater throughput, and similar TCO benefits. ZNS is part of the NVMe 2.0 specification.

NVMe ZNS landed in Linux 5.9 via this pull of block driver updates. Additionally there are other NVMe optimizations, code clean-ups, and fixes too. Over on the MD side, there are several RAID 5/6 fixes as well as RAID 5 stripe fixes and a RAID10 deadlock fix. A few Bcache fixes also squeezed in this cycle.