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].

[0] https://vermaden.wordpress.com/2022/03/25/zfs-compatibility/

[1] https://github.com/openzfsonwindows/openzfs

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adastra22 12 hours ago | parent [-]

NetBSD isn’t a microkernel.

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pests 8 hours ago | parent | next [-]

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.

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Dylan16807 8 hours ago | parent | next [-]

I'm not sure if it originally said small kernel, though I know for sure the italics weren't originally there. The wording is unclear in a couple ways.

	▲	pests 8 hours ago \| parent [-]
		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.

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8 hours ago | parent | prev [-]

[deleted]

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bdhcuidbebe 10 hours ago | parent | prev [-]

[flagged]

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adastra22 10 hours ago | parent [-]

“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.

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pests 8 hours ago | parent | next [-]

Ah, these were dead so I didn’t see this confusion before my comment above.

I read it as:

“I don’t know about other microkernels [that support ZFS], but NetBSD is a small kernel [that supports ZFS]”

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bdhcuidbebe 10 hours ago | parent | prev [-]

[flagged]

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dang 9 hours ago | parent [-]

Can you please edit out personal swipes from your HN comments? You did it repeatedly, and the site guidelines ask you not to: https://news.ycombinator.com/newsguidelines.html.

It's great, of course, to provide correct information. But please do it without putdowns; you don't need them, and they acidify discussion.

	▲	jibal 7 hours ago \| parent [-]
		They also didn't provide any correct information.