- A Linux kernel patch, called epp_boost, improves minimum FPS on Steam Deck by up to 31,8%.
- The function dynamically adjusts the CPU frequency core by core, preventing micro-stuttering.
- Tests with Civilization VI show an improvement in fluidity without affecting energy consumption.
- The patch is still under review, but it could come to SteamOS and other Linux systems with AMD.
Developer David Vernet, an engineer at Meta, has submitted a series of patches to the Linux kernel that introduce a function called epp_boost. This modification affects the AMD P-State driver and aims to fix a common problem in video games: micro-freezes that occur when the CPU reduces its speed during brief pauses in the main thread.
31,8% greater fluidity in critical moments
Initial tests using the Steam Deck and the Civilization VI benchmark show a significant improvement. The lowest frame rate (1% low FPS) increased by 31,8% , resulting in a more stable experience with fewer frame rate drops. The frame rate at the 99th percentile also improved by 4,1%, although the average FPS remained unchanged. This indicates that the improvement is focused on the worst moments, precisely where players experience the most stuttering.
How epp_boost works: a core-by-core surgical adjustment
The problem this patch addresses is a known one: during gameplay, the CPU's main thread briefly pauses while waiting for the GPU to complete an operation. The AMD P-State driver interprets these pauses as low load and reduces the core frequency. When the thread resumes, the CPU takes a moment to regain speed, causing a micro-stutter. epp_boost monitors each core every 10 milliseconds . If it detects that a core has been busy at least 50% of the time, it temporarily changes its power preference to maximum performance. After 300 milliseconds of inactivity, it reverts to the normal setting. This prevents unnecessary extra power consumption and maintains balance with the GPU, which shares the power budget in the Steam Deck's APU.
Although the patch is still under review and requires compiling a modified kernel, its potential is clear. The Steam Deck and any Linux system with AMD Ryzen processors could benefit from this improvement without needing to change hardware, while the development of Steam Deck 2 continues at its own pace. The results with Civilization VI are promising, and it remains to be seen how it will perform with other titles. For now, the community hopes that AMD engineers and kernel maintainers will accept the proposal, which could translate into a smoother gaming experience for millions of users.
