Detecting CPU throttling on over temperature

Daniel O'Connor doconnor at
Wed Sep 9 00:50:54 UTC 2009

On Wed, 9 Sep 2009, Ian Smith wrote:
>  > > Does anyone know if it is possible to determine if this is the
>  > > case? ie is there a way to be informed if throttling has
>  > > occurred?
> Might be easier to hack powerd.c as an existing pretty lightweight
> way of monitoring CPU freq (to log or signal on detected freq lowered
> by throttling, say?) even if you don't need/want it to actually vary
> freq according to load, eg setting idle/busy shift factors to
> 'never/always'?

Hmm, that could work.

It seems odd to me that there is no direct way the BIOS can notify the 
OS it's throttling the CPU though.

Daniel O'Connor software and network engineer
for Genesis Software -
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