The master branch for cp now defaults to copy-on-write on filesystems that support reflinks, which should make copies more efficient if Fedora starts using btrfs: https://git.savannah.gnu.org/cgit/coreutils.git/commit/?id=25725f9d41735d176d73a757430739fb71c7d043. Dolphin and KIO also seem like they will start doing this: https://bugs.kde.org/show_bug.cgi?id=326880, https://invent.kde.org/frameworks/kio/commit/c2faaae697f11ee600989b67b4406981838ae628. Beyond these recent changes, there are many other reasons to use btrfs, such as that Podman has a btrfs driver that might make containers more efficient, that ostree makes limited use of reflinks when they are available, that many filesystem options can be changed and new features and better defaults used even after the filesystem was initially created, that resize operations can be done online, and that there are uniform checksums on all metadata blocks, giving guarantees against corruption. XFS also has reflinks, but lacks many features of btrfs, and switching from ext4 to XFS would mean losing cgroup writeback. XFS would mean no transparent compression too. Switching from ext4 to OpenZFS, even putting aside license concerns from Red Hat, risks kernel releases being delayed or Fedora not being able to release with recent kernels. It makes kernel updates in Fedora dependent on the OpenZFS community releasing new versions compatible with recent kernels fast enough. And this is a concern, because many upstream kernel maintainers indicated they have little interest in avoiding breaking OpenZFS or doing any extra work to get it to work. (See, notably, https://lkml.org/lkml/2019/1/10/733 and https://www.realworldtech.com/forum/?threadid=189711&curpostid=189841.) I appreciate that Fedora’s kernel maintainers release new kernels quickly and think this is something that works well in Fedora. Supporting any out-of-tree modules in Fedora repos, including filesystems, would endanger this. Also, in general, I think it is not a good idea to use things that your upstreams are not interested in, do not want to support, and do not recommend using. Staying on ext4 means not having reflinks, transparent compression, online resize, deduplication, strong guarantees against corruption, and that improved filesystem defaults or new features can be used only by recreating the filesystem and reinstalling Fedora. In consideration of that, I am favorable to the change proposal targeting btrfs in Fedora. _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx
