A Steam Deck AMD Linux patch submitted by kernel developer David Vernet aims to cut the ugly frame-time spikes that can make games feel rough even when their average frame rate looks fine. Vernet described the change on the Linux kernel mailing list, and Phoronix flagged the patch, which targets AMD-based gaming hardware running in Energy Performance Preference mode.
Energy Performance Preference, or EPP, is a CPU power policy meant to balance responsiveness against battery life. On a handheld like Valve’s Steam Deck, that trade matters: leave performance on the table and a game stutters, burn power too freely and the battery pays for it.
What does the AMD Linux patch change on Steam Deck?
Vernet wrote that the current AMD driver can make the wrong call when a game thread is busy but repeatedly sleeps for short stretches. The driver may treat those brief sleeps as a reason to lower the processor’s average performance target. When the thread wakes again, it can resume at a clock speed below what the game needs, adding latency and stretching out the slowest frame times.
That behavior matters most at the bottom of the frame-time chart. Average FPS can hide a bad experience if most frames arrive quickly but occasional frames arrive late enough to be visible as hitches. Vernet pointed to stale frames, higher frame latency, and longer low-end frame generation times as the symptoms the patch is meant to address.
One blunt workaround is to put the processor into performance mode. Vernet said that avoids the problem, but it also throws away the energy savings EPP exists to provide. Another tempting fix, raising the affected thread’s minimum performance target permanently, made low-end performance worse in his testing because CPU and GPU boost behavior interact in less tidy ways than a single slider suggests.
The proposed patch takes a narrower approach. It watches individual cores for cases where a busy thread would benefit from more clock speed, then temporarily moves only that core to the performance setting. Once the workload eases, the core can drop back into EPP’s lower-power behavior.
What did early testing show?
Vernet’s Civilization VI benchmark results showed no change to average FPS, according to his mailing list post. The improvement showed up where players are more likely to feel it: the slow frames.
- Vernet reported a 31.8% gain in the game’s 1% low FPS measurement.
- He also reported 4.1% faster p99 frame generation times, meaning the threshold under which 99% of frames were generated.
Those numbers come from one benchmark, so they should not be treated as a universal Steam Deck upgrade yet. The patch still has to make its way through the Linux kernel process before broader testing can show how it behaves across more games and AMD-based systems.
For Steam Deck owners, the useful part is the direction of the fix. Vernet is not claiming a free average-FPS jump. The patch is aimed at reducing the worst moments while keeping EPP’s power-saving behavior intact, which is exactly the kind of unglamorous kernel work that can keep aging handheld hardware feeling less tired.
This story draws on original reporting from Ars Technica.
