Good question. I don't know about other microkernels, but NetBSD is a small kernel that supports ZFS. The support has been there since the 4.0.5 and 5.3[0], possibly earlier too. I'm not adept at navigating the mailing lists here, but I imagine a good place to learn about the challenges of porting ZFS to a smaller kernel would be the NetBSD and ZFS lists from that era (2008-2009). What NetBSD does today is use a 'zfs' modlue that depends on a 'solaris' kernel modile. The dependency of Solaris primitives is probably one of the major challenges with porting ZFS to any kernel. FWIW, somehow a ZFS port for the "hybrid" kernel in Windows also exists[1].
Who is calling it a microkernel? The post youre replying to calls it a “small kernel” - that does not imply it’s a microkernel tho, right? I didn’t think size has anything to do with it.
I came back to maybe delete my comments as I felt I might have came off harsh, esp before I saw the dead comment chain. No ill will, was confused as well I think.
“I don’t know about other microkernels” implies that NetBSD is also a microkernel. It is not.
Microkernel is not a size distinction. NetBSD kernel may even be smaller in terms of LOC or binary size than some microkernels. Idk. But that is beside the point.
Microkernel is an *architecture*. It is a name for a specific type of kernel design, which NetBSD is not.
"Maybe you should read it more careful, instead adding nothing to the discussion" is crossing into personal attack. So is "Read more, comment less." from your other post in this thread.
Generally speaking, it's not against HN's rules to be wrong. How could it be? We're all wrong about nearly everything. But it is against HN's rules to post disrespectfully, put others down, etc. - for the obvious reason that it poisons community discussion, plus is unnecessary.
It's especially important to follow those rules when one is right about something, because when a post contains both correctness and poison, the poison has has the side effect of discrediting the truth. That is bad for all of us (https://hn.algolia.com/?dateRange=all&page=0&prefix=true&sor...).
[0] https://vermaden.wordpress.com/2022/03/25/zfs-compatibility/
[1] https://github.com/openzfsonwindows/openzfs