A 21-year-old student working as an independent contractor for Valve says they have “fixed” the issue of poor VRAM management on low-end GPUs when using Linux drivers. Natalie Vock, alias pixelcluster, primarily works on RADV (a Vulkan driver for AMD GPUs) and has published a lengthy blog post about new patches to the Linux kernel and KDE.

The patches are targeted at minimizing VRAM usage for 8GB graphics cards, which you may know can struggle to get by in some of the most demanding modern games. A poll we ran last year suggested PC gamers agree that 8GB of VRAM “isn’t enough anymore” – of course, much of this depends on the game, and optimization plays a massive part.

Better allocation of VRAM improves performance in Cyberpunk 2077

Natalie Vock says “Carnage erupts inside the kernel driver” when running low on VRAM, saying that “stutters and slowdowns” are “bound to occur” in this state. Vock has released six new patches, starting with support for CachyOS (a popular Linux distro for gaming that can outperform Windows 11 these days).

Testing done in Cyberpunk 2077 via Steam Play on Linux reveals successful optimization while running an 8GB graphics card. Traditionally, Linux uses GTT to allocate available system memory when VRAM is full. However, Vock says accessing this memory is “typically really, really slow” as it accesses memory over the PCI bus rather than directly from the GPU.

The solution put forward by these patches is better optimization and less reliance on system memory via GTT. Before the patches, Cyberpunk 2077 (GameThread) was using just over 6GB of memory, and a further 1.3GB was pulled from system memory. With the patch applied, GTT usage is halved to just 650MB, and 7.3GB of dedicated video memory is being allocated to Cyberpunk. This results in less latency to help cut down on stutters or slowdowns, as mentioned before.

Before optimization, credit: Natalie Vock

After optimization, credit: Natalie Vock

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On a technical level, Vock’s Linux kernel patches alter how memory is allocated, specifically for the DRM device memory cgroup controller, along with changes to the TTM memory management code. It should be noted that these patches are relevant to AMD graphics cards only, as Nvidia kernel modules do not support DRM device memory cgroups just yet. After all, AMD hardware is still the best for Linux right now.

As alluded to before, using CachyOS (with KDE as your desktop) is the easiest way to enjoy these upgrades, as the CachyOS kernel includes the required patches from version 7.0rc7-2 or newer. If you’re using a different Arch-based distro, then installation can be done manually using the files on Vock’s blog. And if you don’t use KDE, then you can rely on newer versions of Valve’s Gamescope compositor to utilize the optimizations.

All you need to do is use CachyOS’s 7.0rc7-2 kernel, install the packages called ‘dmemcg-booster’ and ‘plasma-foreground-booster’, and you should be good to go.

Natalie Vock

About the Author

Jack Goodall

At PC Guide, Jack is mostly responsible for reporting on hardware deals. He also specializes in monitors, TVs, and headsets and can be found putting his findings together in a review or best-of guide.