In a series of heated e-mail conversations between Linux creator Linus Torvalds and developer Kent Overstreet on the Linux kernel mailing list, Torvalds expressed his strong dissatisfaction with how Bcachefs-related changes are being implemented in the current Linux 6.11 cycle. Here’s what it’s all about.
Overstreet, the developer behind Bcachefs, reached out to Torvalds with significant updates to the file system.
However, Torvalds expressed his frustration, pointing out that the recent submissions were excessively large, deviating from the traditional focus on small, regression-focused updates, highlighting his growing regret over merging Bcachefs into the kernel due to its disruptive development pattern.
Despite the criticisms, Overstreet defended Bcachefs’s reliability, claiming it to be more trustworthy than its counterpart, Btrfs, especially in scenarios where data recovery is crucial.
He cited numerous instances and comparisons where Bcachefs outperformed other file systems, including XFS, regarding robustness and reliability.
Torvalds responded skeptically, suggesting that broader adoption and testing across major Linux distros would be necessary to validate such claims.
He emphasized that the changes proposed by Overstreet were not merely fixes but substantial new developments that also altered non-bcachefs files. This, according to Torvalds, was a step too far from the intended quick fixes that are typical after a new kernel release.
Simply put, only small bug fixes are allowed after the post-merge phase to integrate changes into the current kernel cycle. However, Overstreetโs PR included more than just fixes; it continued to develop new features, which always carry risks. That’s why Torvalds was unhappy with it. As a result, the changes were rejected.
Finally, just to clarify, Bcachefs is a next-generation advanced copy-on-write (COW) Linux filesystem whose support was initially added to the Linux kernel 6.7. It is intended to compete with the modern features of ZFS or Btrfs and the speed and performance of ext4 or XFS.
Currently, the file system is being actively developed. Although it shows great potential with impressive features and strong data reliability, it’s not yet stable enough to be adopted by major Linux distributions as a proven and reliable solution.
Check out the kernel mailing list for further details on the conversation between Torvalds and Overstreet.