Linus Torvalds has just announced the official release of the new Linux kernel 6.16.
Last week was nice and calm, and there were no big show-stopper surprises to keep us from the regular schedule, so I’ve tagged and pushed out 6.16 as planned.
Key Features in Linux 6.16
A quick look at this release reveals that most patches are small fixes, primarily targeting drivers and file systems, but they also include a few important points worth highlighting. Here they are.
XFS Large Atomic Writes
The most exciting new feature in this release is the introduction of support for large atomic writes in the XFS file system, ensuring that multi-block writes either complete entirely or not at all, thereby preventing torn writes.
Ext4 Performance Boosts
Regarding Ext4, the file system sees optimizations in its fast commit path, multi-fsblock atomic writes for bigalloc file systems, and large folio support, delivering up to a 37% speedup in sequential I/O workloads.
USB Audio Offload for Power Savings
After years of development, Linux 6.16 finally introduces USB audio offload support, enabling embedded devices to maintain audio streams while the rest of the system is idle. As you can imagine, this is a significant development for battery-powered devices, as it substantially reduces power consumption.
Intel TDX (Trusted Domain Extensions) Support
Initial support for Intel TDX has landed, offering hardware-based memory encryption for confidential virtual machines. Similar to AMD’s SEV-SNP, TDX protects guest VMs from host interference and physical attacks.
Zero-Copy TCP Transmissions from DMABUF Memory
Following the introduction of the zero-copy receive path in Linux 6.12, the kernel now supports zero-copy TCP transmissions from DMABUF memory. This improves performance for workloads involving GPU or accelerator buffers.
Automatic Weighted Interleaved Memory Allocation
Modern NUMA systems often have memory nodes with varying bandwidth characteristics. Linux 6.16 introduces an auto-tuning policy that dynamically adjusts memory allocation weights based on bandwidth data.
Intel APX (Advanced Performance Extensions) Support
The kernel now supports Intel APX, which doubles the number of general-purpose registers (from 16 to 32) for improved performance and power efficiency.
Easier CPU-Optimized Kernel Builds
For users compiling their own kernels, a new CONFIG_X86_NATIVE_CPU option enables -march=native optimizations, tailoring the build for the local CPU’s capabilities.
Other Notable Improvements
- Futex2 Enhancements: Process-local futex hashes and NUMA-aware futex operations.
- AF_UNIX Coredump Support: Safer core dump handling via Unix domain sockets.
- Btrfs & NFS Upgrades: Better metadata writeback efficiency and new NFS attributes.
- Rust Abstractions: More kernel subsystems now support Rust, including
clk,cpumask, andmmap.
And lastly, something interesting – Torvalds gave a heads-up about the upcoming 6.17 merge window. And guess what?
It’s worth noting that the upcoming merge window for 6.17 is going to be slightly chaotic for me: I have multiple family events this August (a wedding and a big birthday), and with said family being spread not only across the US, but in Finland too, I’m spending about half the month traveling.
He emphasizes that he’s working hard to handle as many PRs as possible early, but he cautioned that due to his busy schedule, the merge window might run a bit late.
For those eager to compile the Linux kernel 6.16 themselves, it’s now available for download at kernel.org. As usual, users of rolling-release distros will be the first to receive the new kernel, with the update expected to be available in their repos over the following weeks.
