Linux 7.3-rc1 Is ‘Big,’ Torvalds Says, With Btrfs Speedups and a Cgroup Scheduling Rework

Updated Oct. 26, 2026, 1:20 a.m. ET: Adds that Linux 7.3 was released as a stable kernel on Oct. 18.

Linux 7.3 is big, and Linus Torvalds says that by itself is the headline. “Nothing really stands out – except for the fact that it’s big,” he wrote when he tagged 7.3-rc1 on Sunday, closing a two-week merge window. About a third of the rc1 patch is AMD GPU code, mostly DCN6 display register headers. “They’re huge. As usual,” Torvalds wrote, adding that once that chunk is masked out, “things look pretty normal.”

Phoronix, which tracked the merge window, noted that part of the size comes from AI coding agents, both through bug reports and patches, and that several old drivers were removed rather than kept alive under that “ongoing noise.”

Scheduler: help for old gaming PCs and hybrid CPUs

The scheduler pull includes Peter Zijlstra’s “flatten the pick” series, which reworks cgroup scheduling, “which has always been problematic and painful.” It adds four weight distribution modes (up, max, concur and tasks), with the most precise and most expensive, concur, as the default, and moves cgroup scheduling to a single runqueue. It was shown to help gaming on a Sandy Bridge CPU paired with a Radeon RX 580. Vincent Guittot’s work to cut latency for short-slice tasks showed large cyclictest improvements, cluster scheduling now handles Intel’s hybrid CPUs correctly, and NOHZ load balancing prefers fully idle cores.

Btrfs gets faster

Btrfs now uses an iomap bounce buffer for direct I/O instead of falling back to buffered I/O, skips hole detection on full fsync for files without holes, and reduces locking around extent readahead. The Btrfs pull request cited roughly 3x and 5x gains in specific areas, and Phoronix’s tests on a Xeon 678X workstation confirmed big improvements in several workloads. Elsewhere in storage, F2FS can flush multiple devices in parallel, raw block devices support RWF_DONTCACHE, KSMBD now works with Apple Time Machine backups, the NTFS driver can read Windows System Compression files, and eCryptfs received security fixes for bugs dating back to its 2006 merge.

Hardware, new and very old

AMD continues preparing for Zen 6, k10temp reports per-CCD temperatures, and a new driver handles LEDs and RGB on the Ryzen AI Halo platform. Intel’s Xe3P graphics for Nova Lake are enabled by default, and initial work landed for Starfire, a rugged Panther Lake derivative. Apple’s M3 Pro, Max and Ultra get initial support, the 2026 Steam Controller gets a kernel driver, and Nouveau gains what NVK needs for Vulkan Video. Valve’s graphics team contributed improvements for systems with little video memory, around 8GB, and DRM format modifier support for older AMD GPUs. There is even a small optimization for Athlon XP-era chips that have SSE but not SSE2.

Phoronix’s early benchmarks on the same Xeon 678X system, run midway through the merge window, found some performance improvements and some regressions, including in graphics tests using Nouveau on an RTX PRO 6000.

Stable release: Linux 7.3 shipped on schedule on Oct. 18, Phoronix reported, with last-week fixes including workarounds for Samsung 990 PRO and 990 EVO Plus SSDs on certain firmware.