How do I disable CPU throttling

[Thomas D. Dean]

On 7/12/21 3:48 AM, Thomas D. Dean wrote:
> I want to run this system at a fixed freq.  It has beefed-up cooling.
> 
> How do I do this?
> 
>  > uname -a
> FreeBSD aorus 13.0-RELEASE FreeBSD 13.0-RELEASE #0:
>     Sat Jul 10 23:47:01 PDT 2021
>     tomdean at aorus:/usr/obj/usr/src/amd64.amd64/sys/GENERIC  amd64
> 
>  From dmidecode:
>   MB: Gigabyte TRX40 AORUS XTREME
>   CPU: AMD Ryzen Threadripper 3970X
>     Max Speed: 4550 MHz
>     Current Speed: 3700 MHz
> 
> # sysctl dev.cpu | grep freq
> dev.cpu.0.freq_levels: 3700/4070 2800/2800 2200/1980
> dev.cpu.0.freq: 2200
> 
> #sysctl dev.cpu.0.freq=3700
> dev.cpu.0.freq: 2200 -> 3700
> 
> === wait 30 sec
> 
> # sysctl dev.cpu.0.freq
> dev.cpu.0.freq: 2200
> 
> Why does dmidecode (via cpu-x) report a different value than
>    sysctl dev.cpu.0.freq?


where does dev.cpu.0.freq_levels get set at boot time?

 > sysctl -n dev.cpu.0.freq_levels
3700/4070 2800/2800 2200/1980

Looks like this is hardwired somewhere.

I searched src/sys/* and found nothing, unless I missed it.  grep'd 
freq_levels, 3700, 4070