Leaving the Desktop Market

Adrian Chadd adrian at freebsd.org
Sun May 4 04:08:27 UTC 2014


TCC is fine.

TCC for doing anything other than _thermal throttling_ these days isn't.

I've been kind of trying hard to avoid touching it as I'm worried
it'll stick to me, but something tells me i'm just going to have to
bite the bullet and grab ownership of this stuff... :(


-a



On 3 May 2014 18:07, Nathan Whitehorn <nwhitehorn at freebsd.org> wrote:
> On 05/03/14 16:59, Kevin Oberman wrote:
>>
>> On Sat, May 3, 2014 at 1:25 PM, Adrian Chadd <adrian at freebsd.org> wrote:
>>
>>> Set it to the lowest available Cx state that you see in dev.cpu.0 .
>>>
>>>
>> Available is not required. Set it to C8. That guarantees that you will use
>> the lowest available. The correct incantation in rc.conf is "Cmax".
>> performance_cx_lowest="Cmax"
>> economy_cx_lowest="Cmax"
>>
>> But, unless you want laggy performance, you will probably also want:
>> hint.p4tcc.0.disabled=1
>> hint.acpi_throttle.0.disabled=1
>> in /boot/loader.conf. Low Cx states and TCC/throttling simply don't mix
>> well and TCC is not effective, as mentioned earlier in this thread.
>
>
> Is there any reason that TCC is on by default, actually? It seems like an
> anti-feature.
> -Nathan


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