Intel Meteor Lake Linux Patches Set to Optimize Default Power Modes

[T0@st]

Phoronix has spotted intriguing new Linux kernel patches for Intel Core Ultra "Meteor Lake" processors—the Monday morning notes reveal in-house software engineers are implementing default power profile adjustments. Meteor Lake CPUs have been operating on a default "balanced_performance" mode since their December 2023 launch—Linux adjustments will affect the processor's Energy Performance Preference (EPP) under Linux (similar to Windows Power Plans). Michael Larabel (Phoronix head honcho) laid out some history: "We've seen EPP overrides/tuning in the past within the Intel P-State driver for prior generations of Intel processors and this is much the same here. The ACPI EPP value is typically a range from 0 to 255 for indicating the processor/system power to performance preference."

He continued onto present day circumstances: "To date though the Intel P-State EPP override/tuning has been focused on the default "balanced_performance" mode while the first patch (from Monday) allows for model-specific EPP overrides for all pre-defined EPP strings. The second patch then goes ahead and updates the EPP values for Meteor Lake so that the balanced_performance default is now treated as 115 rather than 128 and the "performance" EPP is set to 16 rather than 0." Larabel is hopeful that a public release will coincide with the "upcoming Linux v6.9 cycle." Intel software engineers reckon that their tweaks/overrides have produced higher performance results—for "small form factor devices"—while reducing CPU temperatures and thermal throttling. Meteor Lake is considered to be quite energy inefficient when compared to the closest mobile processor architectures from AMD and Apple. Team Blue's next-gen Arrow Lake family is expected to launch later this year, but the current crop of CPUs require a bit of TLC and optimization in the meantime.

"Update default balanced_performance EPP to 115 and performance EPP to 16. Changing the balanced_performance EPP has better performance/watt compared to default powerup EPP value of 128. Changing the performance EPP to 0x10 shows reduced power for similar performance as EPP 0. On small form factor devices this is beneficial as lower power results in lower CPU and skin temperature. This results in reduced thermal throttling and higher performance."

View at TechPowerUp Main Site | Source

 

[Minus Infinity]

Hopefully when Arrow Lake comes out all this will be sorted. Meteor Lake is beta silicon for testing. Skip this for Arrow lake mobile or Luna Lake.

 

[Nhonho]

Any power saving optimization is super important for Intel CPUs, huh... (I'm not kidding).