Among the early pull requests sent out to Linus Torvalds even before the Linux 7.0 kernel officially released on Sunday were the Btrfs file-system updates. This feature-packed CoW file-system is seeing more performance optimizations for Linux 7.1 as well as its shutdown ioctl feature no longer being experimental and a variety of fixes.
On the performance front, Btrfs with Linux 7.1 is speeding up clearing the first extent in tracked ranges for around a 10% throughput improvement on a sample workload. There is also reduced CoW rewrites of extent buffers during the same transaction, avoiding taking the big device lock when updating device stats during transaction commits, fixing an unnecessary flush on close when truncating empty files, and preventing direct reclaim during compressed readahead.
Back in Linux 6.19, Btrfs added an experimental shutdown ioctl. The Btrfs shutdown ioctl is used to set the file-system state as shutdown and for pending operations to attempt to finish them on time and halt. This is similar to the shutdown mechanism of the XFS file-system and with Linux 7.1 it’s being promoted out from behind the experimental flag.
Btrfs is also now reporting file-system shutdown using the FSERROR mechanism, various error handling improvements, and shipping a variety of bug fixes for Linux 7.1.
The full list of Btrfs feature changes submitted for the Linux 7.1 merge window can be found via this pull request.
