I'd be interested in the write amplification since Redpanda went pretty low level in the IO layer. How do you guarantee atomic writes when virtually no disk provides guarantees other than on a page level which could result in destroying already written data if a write to the same page fails - at least in theory - and so one has to resort to writing data multiple times.
3. We adaptively fallocate data to prevent metadata contention on the file handle itself.
4. We issue an fdatasync() - since we are interested in the data being safe (data corruption w/ checksums, etc it's too long to type, but i can expand on a blog post if interested)
5. so imagine a big write (for simplicity) say 1MB. This will get broken up into 16-128KB DMA writes. The last step is an fdatasync for acks=-1 (raft needs this)
There are nuances between each line, but hopefully this gives you a hint on how it's done.
