Warp schrieb:
> clipka <ano### [at] anonymousorg> wrote:
>> If the tools that come with openSUSE 11.2 are right, then on my AMD 
>> Phenom QuadCore box single-threaded apps (e.g. MegaPOV or MCPov ;-)) 
>> perform doubly poor (or actually something around 6.5-fold): Not only do 
>> they use just 25% of the total available processing power
> 
>   Isn't that the correct number for a single-threaded app running on a
> quad-core?

Yes - so far, so good...

>> - by their 
>> failure to do so they also motivate some instance in the system to 
>> further reduce that total, by throttling the CPU clock from 2.3 GHz to 
>> as low as 1.4 GHz (actually 1.15 GHz when idle)...
> 
>   Are you sure it's not doing that because of overheating instead?

Pretty bloody likely not, as the CPU clock indicator goes /up/ when load 
increases - not the typical reaction to thermal issues, is it? :-P

But I found the solution to the riddle: What I saw was only the 
/average/ clock; when not under full load, openSUSE will apparently put 
some of the cores in a kind of standby mode, throttling their clock to 
half speed, while happily running the processor-hungry single-thread app 
on some other core still clocked at full speed.

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