New Linux Patches Aim To Help Improve Intel Meteor Lake Performance & Power Efficiency

There are some new Linux kernel patches that were posted by Intel on Monday that aim to help enhance the overall performance and power efficiency of new Meteor Lake laptop processors under Linux.

The new patches adjust the Energy Performance Preference (EPP) of Meteor Lake chips under Linux. 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.

To date though the Intel P-State EPP override/tuning has been focused on the default "balanced_performance" mode while the first patch mon 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.

The Meteor Lake override patch explains:

"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."

It will be interesting to quantify the performance difference of this change for Intel Core Ultra "Meteor Lake" laptops. Given the timing of the patches they will hopefully be mainlined for the upcoming Linux v6.9 cycle.