Zone size = hardware erase block size?

Posted Jun 2, 2023 11:25 UTC (Fri) by adobriyan (subscriber, #30858)
In reply to: Zone size = hardware erase block size? by DemiMarie
Parent article: Zoned storage and filesystems

> Or are zoned storage devices primarily intended for workloads that bypass the filesystem and handle everything in userspace?

Any application which expects to overwrite data in-place or write data randomly in LBA space is immediately disqualified from using zoned devices and must become small database-like engine (hello, O_DIRECT!) which writes is very precise order (less headache with Zone Append).

So, all classic block/extent filesystems are out. In theory, journalling filesystem may accept zoned device for external journal.

Zone size = hardware erase block size?

Posted Jun 19, 2023 14:10 UTC (Mon) by DemiMarie (subscriber, #164188) [Link]

From my perspective, ZNS essentially moves the flash translation layer from the device to the host. Linux filesystems (other than zonefs) running on zoned storage expose a full POSIX API, and that includes random write support. The question is what zone size will yield optimal performance for workloads that are random-write from a userspace perspective.