high average load and kernel recompilation

[Mario Vukelic]

On Sun, 2009-02-22 at 08:41 +0100, Pol wrote:
> Yes that is the default, but it can be changed. That helps to keep laptop
> from overheating (fan is working, yet it starts only at very high
> temperature)

Got it

> 'powersave' policy  has been set, even when it is mains powered.  That keeps
> frequency at 800MHz. 

Got it

> I have seen no option about throttling.

It's just another word for powersave

> I had made an experimennt to compare loading at 1.7GHz and 0.8GHz and found
> that,  at 1.7GHz, loading lowered of about 1 - 1.5  

Ok, that's to be expected and a good result i guess

> How do you explain that cpu frequency affects loading?

Oh, so you are a bit confused bout what the load actually is :)
Well, the load is calculated in relation to your CPU utilization. If you
put you CPU into powersave, it will be more fully utilized for the same
tasks than if it runs at full speed. So the load will rise.

It's really like comparing 2 computers that are identical except that
the CPU of one of them is half as fast as the other. If you want them to
perform the same tasks, he slower one will have to work a higher
percentage of the time, and thus will have a higher system load.

The Wikipedia article is well-written and should explain it all: 
http://en.wikipedia.org/wiki/Load_(computing)


> > Um. You are running 5 users concurrently from a tc 4200 (possibly even
> > throttled?) and you complain about an average load of 5?
> 
> I don't see any 'throttling' option 

As above, just a different word for CPU powersave

> So, five similar users would rise load to about 1?

Depends on what they are doing. If they are all idle, it should not
change load much. But if as a result 5 times the programs of a single
user end up fightung for CPU time, then yes

> Here firefox takes about 17% of my cpu time.
> Other heavy programs are nspluginviewers (7-17 %), ktorrent (10%), konqueror
> (3-10%, each one of them), Xorg itsef (5-15%)

Add it all up and you are at 100% or not much below