On 08/25/2018 01:26 PM, clipka wrote:
> Am 25.08.2018 um 18:10 schrieb William F Pokorny:
> 
...
> 
> Where do you get those numbers from?

They came off the Wikipedia page Mike posted in this thread.

> 
>  From all I know (and what a quick random peek at the internet
> confirmed), CPU speed is per core, not per package.
> 
> 
...
> 
> What you might be seeing is the CPU not throttling due to overheating,
> but due to being bored.
> 
> Also, if this is a per-CPU speed, it may be averaging over all cores,
> even cores shut down entirely due to being bored.
> 

I wasn't trying to suggest overheating on my machine. My machine is not 
under load - just thunderbird and some xterm windows up. The point I was 
trying to make is how quickly the frequency numbers in /proc/cpuinfo 
change. Suppose Dick's machine starts a new frame. At the very beginning 
things are cool. The CPU (I suspect rather each core as you suggest) 
detects it has meaningful stuff to do so turbo boost it is. Initially no 
reason not to max turbo boost out; things are cool. Suppose it's in 
those first few seconds Dick grabs the frequency values from 
/proc/cpuinfo. They're going to be maxed out. Maybe those maxed out 
turbo frequencies hold for the entire frame, maybe not. We don't really 
know unless we sample at a fairly high rate over time.

Otherwise, I agree my machine is part of the time idling at a lower 
frequency and very likely operating voltage too. I see quite large 
differences between the 4 hyper-threads over time with a bottom at 
800MHz and a top end of 3400MHz, but I've got no idea how the detailed 
accounting works. I expected the hyper-threads to hang together in pairs 
with respect to frequency as there are two per core, but it's not 
reported that way.

> 
...
> 

A couple thoughts I had this afternoon along the lines of your thinking 
there is plenty of cooling to hold the max turbo frequencies. Supposing 
the i5s are aimed mostly at laptops; the cooling in a box enclosure is 
much better. Second, my i7 920 experience with turbo boost is 10 years 
dated.

Bill P.

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