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Comment by lmilcin

6 years ago

The problem with ZFS is that it isn't part of Linux kernel.

Linux project maintains compatibility with userspace software but it does not maintain compatibility with 3rd party modules and for a good reason.

Since modules have access to any internal kernel API it is not possible to change anything within kernel without considering 3rd party code, if you want to keep that code working.

For this reason the decision was made that if you want your module to work you need to make it part of Linux kernel and then if anybody refactors anything they need to consider modules they would be affecting by the change.

Not allowing the module to be part of the kernel is a disservice to your user base. While there are modules like that that are maintained moderately successfully (Nvidia, vmware, etc.) this is all at the cost of the user and userspace maintainers who have to deal with it.

11 comments

lmilcin

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lmm  6 years ago

It isn't just ZFS. All sorts of drivers get broken because Linux refuses to offer a stable API, saying your code should be in the kernel, but also often refuses to accept drivers into the kernel, even open-source code with no particular quality issues (e.g. quickcam, reiserfsv4).

Use FreeBSD where there's a stable ABI and you don't have these problems.

  • zaarn  6 years ago

    Plenty of drivers get rejected because the kernel developers have no confidence that they will be maintained going forward, which would mean the driver would be removed fairly quickly again.

  • the_why_of_y  6 years ago

    FreeBSD does not really have a stable ABI; every major release breaks the ABI, so it's only stable for 2 years.

    https://wiki.freebsd.org/VendorInformation

    • rleigh  6 years ago

      Stable for each major and minor release is still a vast step up on Linux.

      Having a stable ABI for two years is vastly easier to support than an ABI which changes every two weeks. This is reflected by the number of binary modules which are packaged for FreeBSD in the ports tree, and provided by third-party vendors. This stability makes it possible to properly support for a reasonable timeframe, and vendors are doing so.

      4 replies →

unethical_ban  6 years ago

Parent updated their post and my comment is no longer relevant.

  • TallGuyShort  6 years ago

    I don't see how it's an insult to the users. It's saying that not allowing ZFS code to be distributed under the GPL and be maintained as part of the Linux kernel, is a disservice to ZFSonLinux users. Which I think is clearly right.