Android uses EXT4 and seems to have everything in place to support cloned extents. However, the syscalls always return EPERM suggesting that the file descriptor is immutable.
Comments on Which file systems support file cloning
Benjamin
Why would you write that about OpenZFS? It's available as a kernel module for linux. Embrace of OpenZFS only continues to increase on linux.
What you try to hide is that OpenZFS doesn't need special handling for "cloning": it happens by default, at the filesystem level, as a symptom of using filesystem clones.
Unlike btrfs, it has not been intentionally deprecated by major distributions due to lack of data safety.
Benjamin, what I’ve written about OpenZFS is true. It’s not available as part of the Linux Kernel nor managed by the Kernel project. In practice, this means that the Kernel occasionally makes changes that break the OpenZFS module. This has happen on several occasions already.
I think you have misunderstood the premise of the article. I’ve written about file cloning and not file system cloning. It’s a different use case using the same underlying technology. OpenZFS does not support file cloning.
BtrFS is maintained by the Kernel and it sees ongoing work and contributions from major companies all the time. It has not been deprecated.
Seems like OpenZFS will start supporting reflinks soon: https://github.com/openzfs/zfs/commit/48d0e9465de9571a5268f65b7446c693410e0220
Louis