alt Hacker NewsRight now it is not even clear how to interface with SSDs even on a single host, there has been all sorts of attempts to move away from the traditional plain block device model. NVMe has extensions for KV, ZNS, and FDP, all which offer different characteristics. And then there are of course open channel SSDs and some others too. I kinda expect the future foundational IO interface to be more S3-like than block-device or unixy filesystem-like.
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I really wish reviewers would harp on FDP (Flexible Data Placement) and perhaps KV support. FDP supposedly somewhat ate ZNS as a spec, allegedly, but there might be gaps, reasons to keep ZNS.
There's only a small little mention, if we are lucky, on the couple drives that have it (expensive enterprise flagships). It should be a regular sticking point, whether it's there or not. Without pressure it's not going to get regularly available, it feels like.
FDP is so simple. Declare a number for what pool of data you want to write into. Data of the same pool gets written to the same storage such that you can wipe it latter together. It has huge wins though against write amplification! Massive wins. For so close to free.
Some day I want to own a FDP drive. And then I can finally start using the tokio/io-uring support that I contributed! https://github.com/tokio-rs/io-uring/issues/380
The NVMe-KV is more radical. Still worth putting some pressure on, but your drive as KV, as object store, feels harder. Side note, really enjoyed this ceph nvme-kv offload post thing, my favorite tech write up in a while! https://ceph.io/en/news/blog/2026/for-whom-the-door-bell-tol...
Why would it be S3-like? S3 is a very general abstraction on storage. If there's room below the current abstractions, it's below, not above - Linux has drivers for raw flash devices (mtd devices) which gives Linux full control of the program/erase cycle and responsibility for wear-leveling.