On Mon, Jan 15, 2024 at 11:22:36AM +0300, Viacheslav Dubeyko wrote: > Hello, > > I would like to suggest the discussion related to current > status of ZNS SSD support in file systems. There is ongoing > process of ZNS SSD support in bcachefs, btrfs, ssdfs. > The primary intention is to have a meeting place among > file system developers and ZNS SSD manufactures for sharing > and discussing the status of ZNS SSD support, existing issues, > and potential new features. > > The goals of the discussion are: > (1) share the current status of ZNS SSD support, > (2) discuss any potential issues of ZNS SSD support in file systems, > (3) discuss file system's techniques required for ZNS SSD support, > (4) discuss potential re-using/sharing of implemented logic/primitives, > (5) share the priliminary estimation of having stable ZNS SSD support, > (6) performance, reliability estimation comparing ZNS and conventional SSDs. > > Also, it will be great to hear any news from ZNS SSD vendors > related to new features of ZNS SSDs (zone size, open/active zone > limitation, and so on). Do we have any progress with increasing > number of open/active zones? Any hope to have various zone sizes, etc? > > POTENTIAL ATTENDEES: > bcachefs - Kent Overstreet > btrfs - Naohiro Aota > ssdfs - Viacheslav Dubeyko > WDC - Matias Bjørling > Samsung - Javier González > > Anybody else would like to join the discussion? > > Thanks, > Slava There's also SMR hard drives to consider. For SMR, the much bigger zones means that we don't want to burn entire zones on the superblock (plural; we need two so that one will be alive while the other is being erased). We've got provisions for variable sized zones, are SMR hard drives doing anything with this? Or perhaps for a normal, random-overwritable zone at the start?
