On October 5, David Vernet presented a revised AMD P-State proposal at Linux Plumbers Conference in Prague: a dynamic governor would adjust Energy Performance Preference (EPP) for recently busy CPU cores. The design aims to improve frame-time tails and load times on Steam Deck and other AMD-powered systems.

The revised dynamic-governor EPP proposal

The central change is where the EPP adjustment would happen. After review feedback on an earlier driver-level approach, Vernet presented a design in which a dynamic governor would drive EPP. It remains a proposal, not a description of a feature already running on Steam Deck.

That distinction matters for anyone following AMD P-State gaming performance: the October design describes an approach and its intended targets, not a measured result for the revised governor.

How AMD P-State and EPP work

AMD P-State is a Linux CPU frequency-scaling driver that uses Collaborative Processor Performance Control (CPPC) to communicate performance requests and energy preferences to supported AMD processors. EPP is a firmware-facing hint that biases the processor toward performance or energy efficiency. Its documented numeric range is 0–255: lower values favor performance, while higher values favor energy savings. The exact effect depends on the platform.

Support also depends on system firmware. AMD P-State initialization requires a valid ACPI _CPC entry; when initialization is unsupported, the kernel falls back to acpi-cpufreq.

How the proposal differs from the earlier approach

The earlier RFC used a per-core driver heuristic. It sampled a core no more often than once every 10 milliseconds; a core at least 50% busy would receive performance-biased EPP 0. The boost would remain until 300 milliseconds passed without another busy sample.

The revised proposal moves the control toward a dynamic governor that drives EPP. Gaming measurements reported on July 28 concerned the earlier per-core RFC, not the revised governor-level design.

The gaming workloads the proposal targets

Vernet’s proposal focuses on frame-time tails—the longer frames that can make gameplay feel uneven—and load times. Steam Deck is one stated target, alongside other systems powered by AMD processors. Those are aims of the proposal, not outcomes demonstrated for the revised design.

Wine and Proton thread hints were also floated as a possible idea. They are not described as part of the proposed governor design.