The upcoming ACPI support could allow OS like Windows and Linux read CPU frequencies directly without having to estimate them for optimal performance.
AMD's New CPPC HighestFreq Could Improve CPU Scheduling on Future Ryzen Chips, Resulting in Better Responsiveness
Traditionally, OS like Windows and Linux do not have the capability to read the CPU boost frequencies directly from the firmware, but the AMD CPPC HighestFreq could change this forever. The new feature reportedly would allow CPUs to directly report their real maximum boost frequencies to the operating systems through the firmware, which eliminates the need for frequency calculations by the OS.
The change is prepared for the Linux AMD P-State driver and is expected to become a part of the upcoming ACPI 6.7 specification. This might sound a bit technical, but it could be really helpful in improving the thread scheduling efficiency and responsiveness. Since modern AMD Ryzen CPUs already rely heavily on CPPC, or Collaborative Processor Performance Control, the HighestFreq will help the OS to identify the best-performing CPU cores for demanding tasks.
Hence, intensive tasks like gaming can have access to the best cores available, as the scheduler won't treat all cores equally. Instead, the scheduler will prioritize the fastest cores available, which is not possible with the current CPPC implementations. The CPPC does not expose actual frequency information to the OS. Therefore, Windows and Linux rely on abstract performance numbers and interpolation methods to estimate the boost behavior.
This approach is less accurate on newer Ryzen processors, as frequency scaling isn't perfectly linear on all the cores. The HighestFreq solves this limitation and will allow the OS to directly read the maximum frequency values from the firmware. This is convenient because Ryzen processors already use preferred cores, and considering their asymmetric boosting behavior across cores and advanced boosting algorithms, it becomes crucial for the OS to know the exact boost clocks.
For instance, if the scheduler incorrectly estimates which core can sustain the highest boost clock, workloads such as games may not always land on the best cores available. This may not affect the final result drastically, but with better scheduling accuracy, the performance and responsiveness can be improved even further.
News Sources: Gazlog, via Videocardz
About the author: Sarfraz Khan is a hardware reporter with a focus on PC components and the builder community. With years of experience writing about PC hardware and laptops, his work has been featured on several reputable technology publications. Sarfraz's hands-on experience is demonstrated through his first-person accounts of using and comparing different hardware configurations, providing practical and relatable insights for everyday users. His technical analysis is respected by peers in the enthusiast community and has been cited by specialized hardware sites such as Germany's Igor's Lab.
Follow Wccftech on Google to get more of our news coverage in your feeds.
