AMD Core Performance Boost For Linux Getting Per-CPU Core Controls

For the past several months AMD Linux engineers have been working on AMD Core Performance Boost support for their P-State CPU frequency scaling driver. The ninth iteration of these patches were posted on Monday and besides the global enabling/disabling support for Core Performance Boost, it's now possible to selectively toggle the feature on a per-CPU core basis.

These patches have been for handling Core Performance Boost within the AMD P-State driver and also the ability to toggle the feature via the /sys/devices/system/cpu/amd_pstate/cpb_boost interface. Core Performance Boost is for allowing the AMD CPUs to operate within their turbo/boost frequency range. Most users will want to keep Core Performance Boost (Turbo Core) enabled, but those wanting to dynamically reduce/limit their processor power consumption will be able to toggle the support with these pending driver patches.

With the new "v9" patches, the AMD CPB P-State patches have been re-based against the latest Linux power management kernel code, various minor alterations, and now the ability to toggle per-CPU boost control. This new addition lets users toggle individual CPU cores for having Core Performance Boost or not. The new interface is under /sys/devices/system/cpu/cpuX/cpufreq/amd_pstate_boost_cpb for each CPU core. Thus users can tune whether particular CPU cores are boosted above the base frequency.

These newest AMD CPB Linux patches are out for review on the Linux power management mailing list.