.. _on_demand_policy:

On-Demand CPU Frequency Scaling Policy
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The On-Demand policy evaluates the current CPU load using the
:ref:`CPU Load subsystem <cpu_load_subsys>`, and compares it to the trigger threshold defined by the
SoC P-state definition.

The On-Demand policy will iterate through the defined P-states and select the first P-state of which
the CPU load exceeds the defined threshold.

For an example of the on-demand policy refer to the :zephyr:code-sample:`cpu_freq_on_demand` sample.

This policy is reactive. Frequency adjustments occur only after a change in system load has been
observed, so it cannot anticipate sudden high loads. The policy has no notion of task deadlines and
should not be considered as a real-time policy.