We're late into the Linux 3.12 merge window
and other prominent file-systems were already updated
but on Thursday evening the Btrfs updates for the 3.12 kernel were finally published. With the new Btrfs pull does come some notable changes for this next-generation Linux file-system.
With the Btrfs pull request for the Linux 3.12 kernel merge window are a large number of fixes, performance improvements, and clean-ups.
As noted by Chris Mason in the pull request
, there's also subvolume UUID indexing to speed up send/receive with many sub-volumes/snapshots. This indexing works around a performance issue that ended up getting baked into the Btrfs disk format.
Another committed feature for Btrfs in Linux 3.12 is de-duplication (dedup) support while the file-system is mounted and active but not being done inline during file I/O operations.
Btrfs benchmarks on the Linux 3.12 kernel are forthcoming on Phoronix, plus other interesting Linux kernel benchmarks.