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-rw-r--r--Documentation/cpu-freq/governors.txt21
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diff --git a/Documentation/cpu-freq/governors.txt b/Documentation/cpu-freq/governors.txt
index 4dfed30b7fda..66f9cc310686 100644
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+++ b/Documentation/cpu-freq/governors.txt
@@ -167,6 +167,27 @@ of load evaluation and helping the CPU stay at its top speed when truly
167busy, rather than shifting back and forth in speed. This tunable has no 167busy, rather than shifting back and forth in speed. This tunable has no
168effect on behavior at lower speeds/lower CPU loads. 168effect on behavior at lower speeds/lower CPU loads.
169 169
170powersave_bias: this parameter takes a value between 0 to 1000. It
171defines the percentage (times 10) value of the target frequency that
172will be shaved off of the target. For example, when set to 100 -- 10%,
173when ondemand governor would have targeted 1000 MHz, it will target
1741000 MHz - (10% of 1000 MHz) = 900 MHz instead. This is set to 0
175(disabled) by default.
176When AMD frequency sensitivity powersave bias driver --
177drivers/cpufreq/amd_freq_sensitivity.c is loaded, this parameter
178defines the workload frequency sensitivity threshold in which a lower
179frequency is chosen instead of ondemand governor's original target.
180The frequency sensitivity is a hardware reported (on AMD Family 16h
181Processors and above) value between 0 to 100% that tells software how
182the performance of the workload running on a CPU will change when
183frequency changes. A workload with sensitivity of 0% (memory/IO-bound)
184will not perform any better on higher core frequency, whereas a
185workload with sensitivity of 100% (CPU-bound) will perform better
186higher the frequency. When the driver is loaded, this is set to 400
187by default -- for CPUs running workloads with sensitivity value below
18840%, a lower frequency is chosen. Unloading the driver or writing 0
189will disable this feature.
190
170 191
1712.5 Conservative 1922.5 Conservative
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