There is no 'modern' ZFS-like fs in Linux nowadays.
There is no 'modern' ZFS-like fs in Linux nowadays.
zfs is out of tree leaving it as an unviable option for many people. This news means that bcachefs is going to be in a very weird state in-kernel, which leaves only btrfs as the only other in-tree ‘modern’ filesystem.
This news about bcachefs has ramifications about the state of ‘modern’ FSes in Linux, and I’d say this news about the btrfs maintainer taking a step back is related to this.
1. The dm layer gives you cow/snapshots for any filesystem you want already and has for more than a decade. Some implementations actually use it for clever trickery like updates, even. Anyone who has software requirements in this space (as distinct from "wants to yell on the internet about it") is very well served.
2. Compression seems silly in the modern world. Virtually everything is already compressed. To first approximation, every byte in persistent storage anywhere in the world is in a lossy media format. And the ones that aren't are in some other cooked format. The only workloads where you see significant use of losslessly-compressible data are in situations (databases) where you have app-managed storage performance (and who see little value from filesystem choice) or ones (software building, data science, ML training) where there's lots of ephemeral intermediate files being produced. And again those are usages where fancy filesystems are poorly deployed, you're going to throw it all away within hours to days anyway.
Filesystems are a solved problem. If ZFS disappeared from the world today... really who would even care? Only those of us still around trying to shout on the internet.
As for the snapshots, things like LVM snapshots are pretty coarse, especially for someone like me where I run dm-crypt on top of LVM
I’d say zfs would be pretty well missed with its data integrity features. I’ve heard that btrfs is worse in that aspect, so given that btrfs saved my bacon with a dying ssd, I can only imagine what zfs does.