Ssdfs: Flash-friendly log-structured Linux fs for Zoned-Namespace SSDs
lore.kernel.org
lore.kernel.org
ZNS is a pretty simple idea - that it defines small-ish write-blocks called Zones that are explicitly "opened" for writing (but not rewriting) data, which then become "closed" as they fill or are done. Additionally a new Append command let's data be added sequentially, with the driver determining the final address within the zone (typically the host defines the exact location ahead of time when writing).
These capabilities are sufficient to enable a much better use of the SSD than typical access patterns, which SSDFS here is working to leverage.
It's can be hard to appreciate on the surface of it what these small capabilities lead to, but it allows for a far more flash-friendly access pattern, which SSDFS here is leveraging. Zoned Storage[1] has a fairly technical intro page, and a number of videos, which promise a lot. I'm extremely pleased with how strong a foot forward Viacheslav makes as they describe how they came at this problem from the other side, of building a FS to leverage it: I think they did a great job conveying how this capability works in practice & how much better it can be. This is such a thrilling development!