OpenZFS 2.4-rc1 Brings Linux 6.16 Compatibility, Better Encryption Performance With AVX2

Written by Michael Larabel in Linux Storage on 22 August 2025 at 04:26 PM EDT. 46 Comments

The first release candidate of OpenZFS 2.4 is now available for testing of this ZFS file-system implementation for Linux and FreeBSD systems.

OpenZFS 2.4-rc1 adds compatibility for the latest Linux 6.16 stable kernel while continuing to support all the way back to Linux 4.18. OpenZFS 2.4-rc1 on FreeBSD continues supporting FreeBSD 13.3 and newer.

OpenZFS 2.4 is bringing better encryption performance by leveraging Advanced Vector Extensions 2 (AVX2) for AES-GCM, allow setting default user/group/project quotas, new deduplication optimizations, unified allocation throttling, and other enhancements.

Key Features in OpenZFS 2.4.0:
- Quotas: Allow setting default user/group/project quotas
- Uncached IO: Direct IO fallback to a light-weight uncached IO when unaligned
- Unified allocation throttling: A new algorithm designed to reduce vdev fragmentation
- Better encryption performance using AVX2 for AES-GCM
- Allow ZIL on special vdevs when available
- Extend special_small_blocks to land ZVOL writes on special vdevs (#14876), and allow non-power of two values
- Add zfs rewrite -P which preserves logical birth time when possible to minimize incremental stream size
- Add -a|--all option which scrubs, trims, or initializes all imported pools
- Add zpool scrub -S -E to scrub specific time ranges
- Release topology restrictions on special/dedup vdevs
- Multiple gang blocks improvements and fixes
- New dedup optimizations and fixes

Downloads and more details on OpenZFS 2.4-rc1 via GitHub.