proposal: set default lid state to S3, performance/economy Cx states to Cmax

[Warren Block]

On Sun, 4 May 2014, Adrian Chadd wrote:

> [snip]
>
> The easy-to-run test is "sysctl dev.cpu.0.cx_lowest=Cmax" and then use stuff.

It's that "use stuff" step that would preferably be automated.  Is the 
failure mode a lockup, or could a program detect problems?  The idea 
is to get lots of feedback, fast.

> The problem is that we're not getting anywhere near enough exposure to
> this kind of stuff because we don't have it on by default and we don't
> have an active QA group with ridiculous amounts of hardware.
>
> So, I'd like to flip it on and then start blacklisting devices that
> actively don't work in halt states above C1. We're never going to
> cross this bridge fully if we leave things at C1 out of fear.
>
> I'm only suggesting we do this on -HEAD. If it's too scary then we can
> always flip the default back to C1 for 11.0-RELEASE.

Seems reasonable to me.