Last week saw the big set of Bcachefs updates merged for the Linux 6.14 kernel that included the last anticipated big on-disk format change as well as scalability improvements. It was a particularly big pull after Bcachefs missed out on any changes being upstreamed for Linux 6.13. This week a set of follow-on fixes/improvements have been merged for this experimental copy-on-write file-system.
Kent Overstreet sent out a batch of fixes for Bcachefs yesterday and they have already been merged to Linux 6.14 Git without issue.
The changes within this latest Bcachefs pull request included:
– second half of a fix for a bug that’d been causing oopses on filesystems using snapshots with memory pressure (key cache fills for snaphots btrees are tricky)
– build fix for strange compiler configurations that double stack frame size
– “journal stuck timeout” now takes into account device latency: this fixes some spurious warnings, and the main remaining source of SRCU lock hold time warnings (I’m no longer seeing this in my CI, so any users still seeing this should definitely ping me)
– fix for slow/hanging unmounts (” Improve journal pin flushing”)
– some more tracepoint fixes/improvements, to chase down the “rebalance isn’t making progress” issues
Kent also noted in that pull request that for users seeing specific performance issues that are reproducible, he has been working on some new tools for tracking down those Bcachefs performance problems.
These latest Bcachefs fixes are merged and ready to go with the Linux 6.14-rc1 kernel release expected on Sunday. Linux 6.14 stable should be out by late March. Linux 6.14 has also been confirmed already as the planned kernel for Ubuntu 25.04 plus expected to also be powering Fedora 42 out of the box and other spring Linux distribution releases.
