est

[Adam Vande More]

On Sat, Nov 14, 2015 at 6:33 AM, Ian Smith <smithi at nimnet.asn.au> wrote:

>   > > I do
>  > > know that FreeBSD never, so far, runs different cores at any different
>  > > frequencies,
>  >
>  > FreeBSD has supported TurboBoost for years.
>
> Of course.  But we do NOT support setting different CPU frequencies on
> different cores.


Well of course, but that's not what you said initially which is what
prompted my response.


> TurboBoost may clock selected cores up to turbo speed,
> internally determined by microcode, but that has nothing to do with the
> clock speed FreeBSD sets for ALL CPUs, except that the highest (XX01)
> setting is what _enables_ turboboost, and then for ALL cores.
>
> Quoting from the referenced article in question:
>
> https://www.ateamsystems.com/tech-blog/increase-freebsd-performance-with-powerd/
>
> Do I need to detail the several incorrect assumptions at play above,
> regarding FreeBSD's role in interacting with the CPU/s re TurboBoost in
> particular and SpeedStep in general?
>

I do not believe you need to do that.  That link or any other external
source has never been the basis of my response.

I agree the link contains some dubious claims and methodology, however the
heart of it is sort of close enough to accurate.

  > I don't know what you've done to disable a generally useful feature,
>  > but I suggest re-enabling it on your systems if you want better
>  > single core performance.
>
> If you read my post you'd know precisely what I'd done to disable the
> feature that proves less than useful on my particular CPU, running both
> hotter and (marginally) SLOWER on repeatedly timed single-core tasks,
> and considerably hotter on longer multi-core tasks like -j buildworld.
>

You don't have TurboBoost, so what ever results you have can't be applied
to a TurboBoost generalization.  My suggestion for you to re-enable
TurboBoost was also flawed.

Getting rid of my Core2 stuff was a happy time for me.  Don't get me wrong,
it was great when it came around but it's so slow and power hungry compared
to even a sandybridge.


> Don't take my word for it .. please read:
> http://lists.freebsd.org/pipermail/freebsd-mobile/2015-February/013240.html
> then feel free to argue with Warner about advice that worked for me :)
>

I don't even understand what there would be to argue with him about.  His
particular setup may have heat issues when utilizing TurboBoost for an
extended period/load.  My systems do not and they operate in turbo mode
much of the time, at least as far as I've checked it.  It is not something
I monitor continuously.  My current main workstation, a m6600, can have
heat issues if the external video slot is filled.  Without it, it works
great under all conditions.

And the OP's post which started this was nonsensical so I have no comment
in that regard other than EST is not magic.  It doesn't just go off and on.


-- 
Adam