Linux 7.0 Should Fix Nouveau For The Large Pages Support For Better NVK Performance

The open-source NVIDIA driver ecosystem is on the cusp of a significant performance boost, thanks to recent developments in the Linux kernel and Mesa NVK driver. The Linux 6.19 kernel introduced support for larger pages and compression with the Nouveau kernel driver, a feature that promised to deliver substantial performance improvements for open-source NVIDIA graphics. However, due to bugs, the Mesa NVK driver had to disable this functionality shortly after its introduction.

Red Hat engineer David Airlie has been at the forefront of addressing these issues. In a recent blog post, Airlie outlined his latest bug fixes to the Nouveau kernel driver code. One fix addressed a suspend issue with a NVIDIA RTX 6000 Ada GPU, while the other tackled the larger pages support. Airlie's work has been crucial in identifying and resolving the Nouveau kernel driver issues that were preventing the feature from being utilized effectively.

Airlie's fixes are currently queued up in drm-misc-next-fixes, which means they will be included in the next kernel cycle. The Linux 6.20~7.0 kernel merge window is expected to kickoff next week, and once all of the Direct Rendering Manager "-next" changes are submitted, the fixed-up Nouveau larger pages support should make it into the kernel during that two-week merge window.

The restoration of large pages and compression support in the Nouveau driver is expected to provide "good speedups for games," according to Airlie. This is particularly significant for the open-source NVIDIA gaming community, as it could lead to more competitive performance compared to proprietary drivers.

For those unfamiliar with the technical details, large pages (also known as huge pages) allow the system to use larger memory pages, which can reduce the overhead of memory management and improve performance, especially in graphics-intensive applications like gaming. Compression, on the other hand, can help reduce memory bandwidth usage, further enhancing performance.

The journey to this point has not been without its challenges. The initial introduction of the feature in Linux 6.19 was met with enthusiasm, but the subsequent discovery of bugs that forced the Mesa NVK driver to disable the feature was a setback. However, the persistence of developers like Airlie has ensured that these issues are being addressed, and the feature is on track to be restored in the upcoming kernel release.

This development is a testament to the collaborative nature of the open-source community. It highlights the importance of continuous testing, feedback, and iteration in the development process. The fixes being implemented by Airlie and others are not just about resolving bugs; they are about optimizing the entire stack to deliver the best possible performance for users.

As we look forward to the Linux 6.20~7.0 kernel release, the restoration of large pages and compression support in the Nouveau driver is a significant milestone. It underscores the ongoing commitment to improving open-source graphics drivers and ensuring that they can compete with their proprietary counterparts. For gamers and developers alike, this is a development worth watching closely, as it could have a tangible impact on the performance and usability of open-source NVIDIA graphics solutions.