Not sure why you’d consider criticism of ZFS to he snark. Running any filesystem outside the mainline kernel is a bunch of extra effort and I’m sure as a ZFS user you’d know that. I’m not sure how ZFS could be “hugely successful” after two decades and still not in the Linux kernel.

> Running any filesystem outside the mainline kernel is a bunch of extra effort and I’m sure as a ZFS user you’d know that

zfs-dkms makes usage simple since openzfs backwards compatible down to 3.xx kernels. no need to mix match zfs with kernel versions anymore.

the only drawback is that you may not get to use the lastest kernel until openzfs mantainers give it the thumbs up (no 6.xx compatible release yet), but that's not "a bunch of extra effort".

and that's only a problem if you want to be in the bleeding edge. LTS kernel users wouldn't know about it.

> I’m not sure how ZFS could be “hugely successful” after two decades and still not in the Linux kernel.

"There is no way I can merge any of the ZFS efforts until I get an official letter from Oracle that is signed by their main legal counsel or preferably by Larry Ellison himself that says that yes, it's OK to do so and treat the end result as GPL'd" -Linus Torvalds

sound like a legal issue more than technical.

IIRC the kernel module also uses a compatibility layer, which is also unlikely to ever be accepted.

So its a technical issue too

LTS kernel users don’t generally have access to ZFS - RHEL won’t touch it with a ten foot pole and very few large organisations use Ubuntu.

Linux users are constantly using drivers outside of the mainline kernel. Whether it’s graphics cards, radio drivers (things have gotten better in that regard but Bluetooth is support is still terrible) or FUSE file systems.

The difference with ZFS is that the code is kernel-ready but there’s just some licensing worries (understandable ones) that stop it from being mainlined.

I’ve been running ZFS on Ubuntu Server for several years now and frankly ZFS is the only part of that entire system that doesn’t suck (in my opinion). I’d switch back to FreeBSD in a heartbeat if I didn’t need Docker support but credit where credit is due, Ubuntu’s ZFS support has been really good.

Edit: just to add, I’ve got nothing against anyone who does enjoy Ubuntu Server. It’s just not a Linux distro I personally have much fondness for.