Linux 7.3 Released with Major AMD VRAM Optimizations, Faster CPU Scheduling, and File System Improvements

Linus Torvalds has officially announced the release of Linux 7.3, marking the arrival of a major mainline kernel update that brings a comprehensive array of performance enhancements, hardware bring-ups, and architectural refinements. The new kernel release serves as the foundational operating system engine for the recently launched Ubuntu 26.10, and industry expectations point toward it being designated as the next Long Term Support (LTS) version.

Writing on the Linux kernel mailing list to announce the milestone, Torvalds maintained his characteristic wit, noting, "It’s Sunday afternoon, and this week I somehow kept my wits together long enough to keep track of the day of the week, so the release isn’t randomly delayed. Will wonders never cease?" With the release officially out the door, the broader open-source community can now turn its attention to analyzing the deep technical changes embedded within the latest mainline code tree.

According to statistical figures compiled by LWN, Linux 7.3 represents a massive collaborative effort, featuring 18,765 non-merge commits contributed by more than 3,000 developers from across the global technology ecosystem. Notably, the development cycle saw contributions from 807 first-time kernel developers, signaling a healthy and ongoing influx of fresh engineering talent into the core operating system project.

Linux 7.3 Features

Better AMD Performance with Low VRAM

One of the standout performance features in Linux 7.3 addresses a common bottleneck for users operating AMD graphics hardware with limited video memory, or VRAM. In previous kernel iterations, when VRAM capacity became exhausted during multi-application workflows, the subsystem handled resource allocation on a strict first-come, first-served basis. Under that older paradigm, applications launched later—such as a demanding 3D game—could be aggressively pushed off the graphics card’s ultra-fast dedicated VRAM and forced into slower system RAM via the Graphics Translation Table (GTT).

Linux 7.3 introduces a sophisticated resource allocation approach that allows the kernel to evict unprotected background data belonging to other applications out of VRAM dynamically. This frees up crucial memory pools to accommodate high-priority execution requests, such as a game demanding protected memory space. Valve engineer Natalie Vock spearheaded this particular engineering effort. In rigorous testing involving the title Indiana Jones and the Great Circle, the algorithmic changes successfully enabled the game to maintain stable performance on an 8GB graphics card even when graphics settings were pushed to a threshold requiring close to 9GB of VRAM. Developers note that this represents only an initial phase of broader VRAM management overhauls planned for upcoming kernel cycles.

Older AMD GPU and CPU Fixes

The kernel development team has continued its sustained focus on refining support for legacy and mature hardware architectures. In Linux 7.3, DRM format modifiers—essentially structural metadata labels describing how image buffers are organized—are now natively supported on AMD Radeon graphics cards stretching back to the HD 7000 series, which utilizes the GCN 1.0 architecture. This integration yields performance gains in specific workloads and enhances compatibility with Vulkan-based Wayland compositors.

Concurrently, retro hardware enthusiasts running vintage AMD Athlon XP processors, alongside certain legacy Intel Pentium III and Celeron CPUs, can now properly leverage the SFENCE instruction for memory-write ordering without requiring SSE2 instruction set support. This change rectifies an overly restrictive architectural requirement present in preceding kernel versions. While the release contains numerous other hardware enhancements for unreleased components, core developers have heavily prioritized tuning the experience for equipment currently deployed in the field.

Faster cgroup CPU Scheduling

Resource distribution and system responsiveness under heavy multitasking loads have also received a fundamental tune-up. Linux 7.3 reshapes how the kernel divides processor time among various applications and system services, striving to prevent interactive stutter when background processes aggressively compete for execution cycles.

The core scheduler now efficiently allocates CPU time among distinct groups of processes operating primarily on the central processor, moving cgroups to a unified run queue to minimize systemic latency. A new execution mode designated as concur has been established as the default setting, though administrators retain the flexibility to revert to legacy scheduling behavior if required. In his preliminary cover notes, the maintainer indicated that the new default was chosen with the expectation that it would positively impact a significantly larger cross-section of users.

Earlier baseline benchmarks conducted by scheduler maintainer Peter Zijlstra demonstrated striking improvements under synthetic stress testing. In scenarios involving eight heavy background processes running concurrently, a test application saw its minimum frame rate jump dramatically from 3.8 frames per second to 20.6 frames per second, while average frame rates climbed from 48 frames per second to 57.2 frames per second.

Faster Ext4 Reads and Writes

Ext4, which serves as the default file system for Ubuntu and countless other Linux distributions, benefits from a series of targeted performance optimizations. Parallel direct I/O write operations, which bypass the traditional page cache, execute with higher efficiency alongside accelerated fallocate() handling, while an intermittent buffered-write regression has been fully resolved.

Furthermore, both the ext4 and XFS file systems deliver faster execution speeds for small, direct disk read requests. Empirical evaluations conducted by a ByteDance engineer utilizing a high-performance PCIe Gen5 NVMe solid-state drive highlighted a notable surge in 4K random-read performance, rising from 1.92 million operations per second to 2.19 million operations per second. Even higher throughput gains were unlocked when pairing the file system enhancements with io_uring to manage large batches of asynchronous read requests simultaneously.

Storage flexibility also expands with updates to file system drivers. The ntfs3 driver gains rudimentary support for alternate data streams, enabling files to retain auxiliary metadata alongside their primary contents. Meanwhile, the newer ntfs driver, which has remained an optional inclusion since the release of Linux 7.1, introduces read-only support for Windows overlay filter compression.

Steam Controller, MSI Claw, and More Hardware Support

Peripheral compatibility broadens significantly in Linux 7.3. The 2026 iteration of the Steam Controller receives its initial driver implementation, and Valve has contributed a dedicated driver for the MSI Claw handheld gaming device. Additionally, the driver governing the original Steam Controller has been expanded to support supplementary internal sensors.

Audio hardware integration sees similar attention. The HyperX QuadCast 2 USB microphone now accurately reports its active mute state, and the operating system gracefully handles hot-plugging events for the microphone attached to the Logitech PRO X Wireless headset. The broader Logitech HID driver subsystem has been updated to support HID++ 2.0 reprogrammable buttons, a feature that will directly benefit owners of peripherals like the Logitech Signature M650 mouse.

Professional audio and computing gear are also well-represented. The high-end Pioneer DJ DJM-S11 two-channel DJ mixer gains native USB audio support, persistent USB passthrough anomalies on the M-Audio Venom synthesizer are resolved, and internal microphones are now successfully detected on TUXEDO laptops built upon the TongFang XxAF5xxx chassis base.

To prevent misconfigurations, the kernel now validates USB-C cable capabilities for alternate modes, such as DisplayPort and Thunderbolt connectivity, before attempting to initialize them. This proactive handshake eliminates historical issues where unsupported cables were erroneously assumed to possess advanced data capabilities. Motherboard monitoring infrastructure has also grown, with hardware sensors on modern ASUS boards—including the ProArt Z690-CREATOR WIFI and ROG CROSSHAIR X870E HERO—fully reporting their telemetry data. Support has likewise been extended to Realtek’s 8922DE and 8922DE-VS PCI wireless networking adapters.

Apple M3 Pro, Max, and Ultra Support

Hardware support for Apple Silicon architecture moves forward with foundational, early-stage bring-up code for the M3 Pro, M3 Max, and M3 Ultra processor variants, following the introduction of base M3 support in Linux 7.2. Operating system developers emphasize that this initial support is immature and does not yet offer the polished, out-of-the-box usability found in the more mature M1 and M2 driver implementations.

In other Apple-centric developments, the kernel’s native ksmbd network file server gains optional support for Apple Time Machine protocols, permitting macOS clients to seamlessly utilize Linux-based network storage arrays for local system backups. Additionally, compatibility with Apple’s Studio Display has been refined for AMD graphics hardware through improvements in the AMDGPU display core driver, allowing desktop window compositors to properly recognize the tiled 5K display panel as a cohesive unit rather than treating it as two distinct, independent screens.

Among systemic architectural changes, Linux 7.3 incorporates a substantial body of LLM-assisted code designed to assist hypervisors in tracking virtual machine memory consumption. By flagging unused memory page ranges as inaccessible, the subsystem can effectively reclaim cold memory pages to optimize virtualization density.

How to Get Linux 7.3 on Ubuntu

Ubuntu 26.10 integrates Linux 7.3 directly into its installation media and will roll out the final stable kernel packages to existing user systems via standard software update channels in the coming days. Users operating the Ubuntu 26.04 LTS release series will receive the updated kernel via the hardware enablement (HWE) update path scheduled for early 2027.

While Canonical provides mainline kernel builds for testing purposes on other Ubuntu distributions, developers advise caution, noting that raw mainline packages lack specific distribution-level patches, carry no formal support guarantees, and omit localized security backports. For standard desktop and server deployments running stable releases, retaining the default supported kernel remains the recommended path.

With the release cycle finalized, the merge window for Linux 7.4 is slated to open immediately, setting the stage for the next phase of open-source kernel development.