News: 0001469350

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Updated Intel Meteor Lake Tuning For Linux Shows Huge Performance/Power Improvements

([Intel] 2 Hours Ago EPP Tuning)


It's like magic with one line of code changed in the Linux kernel that Intel is reporting up to 19% performance improvement for Intel Core Ultra "Meteor Lake" and up to an 11% improvement in performance per Watt. Or in another EPP mode, the power consumption during video playback can be reduced by 52%!

Intel Linux engineer Srinivas Pandruvada sent out a patch today for updating the Intel Meteor Lake Energy Performance Preference (EPP) value within the Intel P-State CPU frequency scaling driver. The ACPI EPP value is a range from 0 to 255 for indicating the processor/system power to performance preference. Back in February Intel changed [1]the Meteor Lake EPP from a value of 128 to 115 when operating in the default "balance_performance" mode but that turns out to not be entirely ideal. The one-line patch put out today bumps it from 115 to 64 and is yielding nice gains in performance and power efficiency.

With the revised EPP value, the Intel Meteor Lake performance improved by 19% for the Speedometer web browser benchmark. The WebXPRT 4 browser benchmark improved by 12%, 3DMark Wild Life Extreme improved by 3%, and Geekbench's multi-threaded test went up by 2%. Meanwhile the performance-per-Watt increased by 11% with 3DMark Wild Life and 5~6% in the web browser benchmarks.

[2]

The patch also tunes the value of the balance_power EPP value. In changing that default, video playback power consumption is reduced by 52%! Meanwhile the Microsoft Teams video conference power consumption dropped by 35% with that EPP adjustment. Those power improvements in particular are huge but the 5~19% balanced_performance improvements are significant as well for the latest Intel Core Ultra laptops.

[3]This patch provides that updated tuning magic for the Intel Meteor Lake SoCs with the P-State driver. Hopefully the patches will be merged for Linux v6.11 if not being submitted early as a "fix" for the current 6.10 cycle... Following that was also [4]this patch so that Intel Arrow Lake will follow the same new EPP defaults as Meteor Lake.

Once the refined Meteor Lake EPP patch is merged, I'll be running a more extensive set of benchmarks on my [5]Core Ultra 7 155H system to look at the power and performance difference in a larger set of workloads.



[1] https://www.phoronix.com/news/Meteor-Lake-EPP-Linux-Tuning

[2] https://www.phoronix.com/image-viewer.php?id=2024&image=meteor_lake_office_lrg

[3] https://lore.kernel.org/lkml/20240606181214.2456266-1-srinivas.pandruvada@linux.intel.com/

[4] https://lore.kernel.org/lkml/20240606182748.2457952-1-srinivas.pandruvada@linux.intel.com/

[5] https://www.phoronix.com/search/Core+Ultra+7+155H



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