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I'm using a Raspberry Pi board and I would like to build a real time system. During the kernel configuration, I found the CONFIG_CPU_FREQ option, which (from the help section)

allows you to change the clock speed of the CPU on the fly. This is a nice method to save power, because the lower the CPU clock speed, the less power the CPU consumes.

That's a nice approach to consume less power but in real time applications this could lead to unpredictable behavior and high latencies.

Xenomai developers suggest to disable CONFIG_CPU_IDLE because (from here)

it allows the CPU to enter deep sleep states, increasing the time it takes to get out of these sleep states, hence the latency of an idle system. Also, on some CPU, entering these deep sleep states causes the timers used by Xenomai to stop functioning

I was wondering if disabling these two options could damage the cpu since the board does not come with a heat dissipation system? I imagine that, without these options, the cpu will be more reactive but it sounds like a CPU-Seppuku to me.

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