Re: RELENG_13 and min cpu frequency

On 11/20/2022 2:37 PM, Ian Smith wrote:
> Thanks Kevin.  I went hunting through freebsd-acpi archives, and found your related comments in
>
> https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=264775
>
> Seems we need some overview on what FreeBSD can and can't do regarding changing CPU speeds, or whether it's even appropriate to try doing so on these latest processors?
>
> I'm well behind; few years ago there wasn't even the concept of different cores running different frequencies.
>
> Maybe the best we can do with these is making sure that fans are up to keeping the system cool enough ..
>
> Not that this helps mike's problem with apparent packet loss, but it's hard to see if that may be related.
>
> cheers, Ian

Hi Ian and Kevin,

I was playing with a few little scripts to try and keep the core 
activity high, but its doesnt make sense as to why one thing is better 
than another. Doing something like dd if=/dev/urandon bs=1024k count=5 | 
sha512 does NOT seem to make too much of a difference  in a loop.  And 
doing

sysctl -a dev.cpu. | grep freq

seems to make the cpu stay higher / longer than the dd. Perhaps due to 
some kernel land  vs userland calls. Not sure.

     ---Mike