Yeah, Linux is never going to merge something CDDL into the mainline short of people achieving porcine aviation. Among other things, booting from ZFS on Linux

Yeah, Linux is never going to merge something CDDL into the mainline short of people achieving porcine aviation. Among other things, booting from ZFS on Linux can still be an experience with rough edges - I think one distro makes it easy to do from the installer (Slackware?), but otherwise you get to follow instructions which are opaque to someone not already familiar with running Linux, and debugging can be weird even if you are (the most common thing I've seen is the initramfs failing to import the pool and dropping to a rescue prompt, then succeeding at importing there - for a variety of reasons, usually not "the disks weren't spun up yet when it tried importing" any more). There's also the caveat that frequently ZFS gains feature flag support faster than GRUB2 gets updated to boot from those features, particularly since you can't just shove CDDL code into GRUB2, so you get to reimplement the wheel, and zpool upgrade/zpool set doesn't currently warn you that you're gonna make your pool unbootable if you turn on those features. I'm not a distro maintainer or anything of the sort, but between the above rough edges and concerns about redistributability of CDDL modules compiled against the Linux kernel and patents, I'm not surprised that people shy away from it unless $BIG_CUSTOMER throws a lot of money at them to make it a first-class citizen. (I'm also really curious, consequently, why Canonical is diving headfirst onto the wagon...)