#PDF slides on #FDP, "flexible data placement" to reduce write amplification on #Flash #storage. Apparently this is the thing they're pushing to replace #zoned-storage? It has a stateless API (unlike ZNS on Flash) but requires feedback to guarantee WAF = 1.
on 02025-10-21"f2fs" is the #Flash friendly #filesystem for #zoned-storage. “F2FS is a file system exploiting NAND flash memory-based storage devices, which is based on Log-structured File System (#LFS). The design has been focused on addressing the fundamental issues in LFS, which are snowball effect of wandering tree and high cleaning overhead.”
on 02025-08-24in ZNS #zoned-storage a zone must be a power-of-2 number of LBAs, unlike in ZAC and ZBC #PDF #toread
on 02025-08-24#NVMe #zoned-storage “A zoned namespace is a namespace that is associated with the Zoned Namespace Command Set. A zoned namespace is divided into a set of equally-sized zones, which are contiguous non-overlapping ranges of logical block addresses. (...) A zone type of Sequential Write Required requires the set of logical block addresses of a zone to be written sequentially.”
on 02025-08-21Youtube #video by Snørling introducing a #zoned-storage command set
on 02025-08-21“Zones in #zoned-storage devices must be written sequentially. This is called the sequential write constraint. Each zone in the device address space has a write pointer that keeps track of the position of the next write. Data in a zone cannot be directly overwritten: before being overwritten, the zone must first be erased using a special command (zone reset).” #SSD #Flash #SMR
on 02025-08-21