I absolutely love ZFS. I use it on FreeBSD for all disks on the whole system, including the ones that FreeBSD itself is installed on, and I use it with some disks on Linux and with most of my external disks with macOS.
In an alternative universe, Mac OS X would have gotten ZFS shipped with the base install back in 2007, and presumably we’d then still have that to this day. In our universe that ended up not happening even though it was supposed to :/ https://mjtsai.com/blog/2025/04/28/revisiting-zfs-for-mac/
I really would have loved to have the whole of macOS running on ZFS. But at least using ZFS from homebrew on macOS to have ZFS on external disks is the next best thing after that, and which we do have.
I'd love ZFS a lot more if it weren't for the ARC. Using ARC means that ZFS caches stuff outside the kernel page cache. That in turn means that sendfile is no longer zero-copy when data originates on ZFS, making it a non-starter for content drives for our CDN workload.
Shipped, thanks to you: the copy-on-write room now opens its sources in a side panel. Your comment went from here to production in about four hours. Others rooms to come. The rendering is far better!
Building a museum when you self admit you don't understand the internals that well... seems like a conflicting goal? If you're showing off to educate then how can you do that if you don't understand it?
We know the answer, obviously. I can't trust how much of this was something an AI said vs something you actually did seriously look over. At the very least, all of the text on this should've been in your own words, I think. Otherwise this is just show and tell of some prompts.
I wish I could enjoy tech demos anymore, but now they feel so hollow. Which is a real loss from the age of LLMs. I used to enjoy reading the dolphin EMU progress report for years. I wonder what they're up to.
As a mere operator, I've been fascinated by ZFS ever since I first heard of it 15+ years ago. It seems so elegant, like it really is the last generalist filesystem one would ever need. Performant, reliable, fundamentals easy to comprehend. I've never tried managing LVM configs because zpools and raidz are just so damned easy. Native encryption. Datasets can be as simple or as complicated as you need them to be. send/recv dataset syncing at the block level vs having to decrypt and sync files individually.
A lot of this goes over my head as someone who isn't familiar with filesystem internals, but I appreciate the effort and the homage to a great tool.
So many really brilliant people keep saying this, so I don't doubt that it's true. Can you explain to an ordinary user why ZFS isn't everywhere? It seems to be a marvel, yet ext4 lives on.
I would say (in no particular order) that the CDDL license is not innocent, ext4 is good enough for many usages, cost ? ZFS is RAM hungry ...
but ZFS is well present where it means most (NASes , Proxmox , backups to tell some)
ext4 is in the kernel, and ZFS has this weird ARC thing (its own filesystem cache; I don't know why it can't just use Linux's page cache). Those are the (frivolous) reasons I don't use it on my computers.
If it weren't for those two factors I think it'd be a lot more popular (and Btrfs might not exist).
Thanks, that's exactly the reader I'd like to reach, and you're not the first to say it goes over your head. Honestly, I'm still trying to figure out who it doesn't go over the head of. Matt Ahrens, maybe? ^^ Next is a "start here" route: one plain question per room, answered before any code. Copy-on-write and snapshots are probably the best rooms to start with today.
In an alternative universe, Mac OS X would have gotten ZFS shipped with the base install back in 2007, and presumably we’d then still have that to this day. In our universe that ended up not happening even though it was supposed to :/ https://mjtsai.com/blog/2025/04/28/revisiting-zfs-for-mac/
I really would have loved to have the whole of macOS running on ZFS. But at least using ZFS from homebrew on macOS to have ZFS on external disks is the next best thing after that, and which we do have.
An editing pass to make the prose less "punchy" would be great.
We know the answer, obviously. I can't trust how much of this was something an AI said vs something you actually did seriously look over. At the very least, all of the text on this should've been in your own words, I think. Otherwise this is just show and tell of some prompts.
I wish I could enjoy tech demos anymore, but now they feel so hollow. Which is a real loss from the age of LLMs. I used to enjoy reading the dolphin EMU progress report for years. I wonder what they're up to.
You keep using those words. I don't think it means what you think it means.
A lot of this goes over my head as someone who isn't familiar with filesystem internals, but I appreciate the effort and the homage to a great tool.
I think maybe that's the one feature that's iffy? Theoretically great but bad history of bugs. (Unfortunately)
If it weren't for those two factors I think it'd be a lot more popular (and Btrfs might not exist).