CPU Perf & Power Mgt

[David Chisnall]

On 20 Aug 2015, at 17:44, Justin Hibbits <jrh29 at alumni.cwru.edu> wrote:
> 
> There was a working group at BSDCan this year on power management, and
> what we need to / can do to bring it up to par with the modern world.
> Unfortunately, I haven't had any time lately to work on it, but you
> can read the notes at
> https://wiki.freebsd.org/201506DevSummit/ClockDomains
> 
> In short, the goal is to add infrastructure to the kernel to support
> overall power management of the system, scaling beyond cpufreq/powerd.
> Looking for volunteers who could do some of this, due to my lack of
> time to work on it.

We also had a power management meeting at BSDCam this week.  Robin presented some slides (though the download seems to be broken for me at the moment):

https://wiki.freebsd.org/201508DevSummit?action=AttachFile&do=get&target=power-management-for-freebsd-bsdcam-2015.pdf

This includes the design that ARM is trying to push into Linux, which looks like it would be adaptable to FreeBSD (and, on the plus side, our complete lack of existing power management in the kernel already means we don’t already have the legacy stuff that they are fighting in Linux).  The goal is to have the scheduler drive all of the (CPU) power management.  Any volunteers to work on this are welcome - ARM people are happy to provide advice.

David