Re: Changing temperature trip points

Pavel Machek
2002-11-03T22:15:32Z

Hi!

> > PS: Polling rate has strong effect on how passive works. If you set
> > it too fast it will basically only use "max performance" and "max
> > throttle", which is not what you want.
> No, it doesn't: the _trend_ is deciding, and not the fact that the temp is
> above the limit. additionally, polling is used automatically when passive
> cooling a.k.a. "throttle || performance" is used. Patch will follow soon.

AFAICR, its something like a * temperature + b * trend.

Assume your polling frequency is 1msec, and passive limit 50C.

t: Temp is 50C, machine is cool at P0:T0.
t+1 msec: Temp is 51C. Trend is +, temperature is over, machine goes P0:T1.
t+2 msec: Temp is still 51C (1 msec is too little time for temp to
change), trend is no change, but temperature is still over, machine
goes P0:T2.
t+3 msec: Temp is still 51C (2 msec is too little time for temp to
change), trend is no change, but temperature is still over, machine
goes P0:T3.
at t+7 msec machine reaches P0:T7.
at t+1000msec cpu cools down, and you reach P0:T0 in 7 msec.

Not good.
Pavel
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