How do I disable CPU throttling

Paul Procacci pprocacci at
Tue Jul 13 19:00:23 UTC 2021

On Tue, Jul 13, 2021 at 12:56 AM Thomas D. Dean <tomdean at>

> On 7/12/21 8:17 PM, Paul Procacci wrote:
> >
>  > sysctl dev.cpu.0 | grep freq
> dev.cpu.0.freq_levels: 3700/4070 2800/2800 2200/1980
> dev.cpu.0.freq: 2200
> These numbers are in GHz.
> What I want to do is understand where the numbers 3700 and 4070 come from.
You aren't looking at the right place.  This information is offered by the
CPU and it's the
CPU's documentation that you'll find the information you're looking for.

If using Intel for instance, you'd be interested in reading about SpeedStep.
Along with that, you'll want to understand ACPI, which is essentially the
software side, or
programmable interface to SpeedStep among other things.

For instance, bit 22 in edx after a `cpuid` instruction with eax set to
0x01 will tell ya if
if the cpu even supports acpi.


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