On 10/29/24 9:55 PM, Christoph Hellwig wrote:
For the temperature hints the only public user I known is rocksdb, and
that only started working when Hans fixed a brown paperbag bug in the
rocksdb code a while ago. Given that f2fs interprets the hints I suspect
something in the Android world does as well, maybe Bart knows more.
UFS devices typically have less internal memory (SRAM) than the size of
a single zone. Hence, it helps UFS devices if it can be decided at the
time a write command is received where to send the data (SRAM, SLC NAND
or TLC NAND). This is why UFS vendors asked to provide data lifetime
information to zoned logical units. More information about UFS device
internals is available in this paper: Hwang, Joo-Young, Seokhwan Kim,
Daejun Park, Yong-Gil Song, Junyoung Han, Seunghyun Choi, Sangyeun Cho,
and Youjip Won. "{ZMS}: Zone Abstraction for Mobile Flash Storage." In
2024 USENIX Annual Technical Conference (USENIX ATC 24), pp. 173-189.
2024 (https://www.usenix.org/system/files/atc24-hwang.pdf).
Bart.
