Re: Performance regression in v3.14

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> That is not true. Yes, and due to the setpoint being less than
> 100, which is needed or the driver won't work at all, there is
> a tendency to drive the target pstate upwards.
> However that is tempered by both the PID proportional gain,
> and ultimately integer math. More importantly, the CPU
> itself tells the driver when it is operating below the target
> pstate and driver responds.
> Additionally, the tendency to drive up the target pstate
> too much is exasperated by some extra rounding up at a
> couple of spots. Dirk has a pending fix.
> > And a few iterations
> > later, we will reach max (possible) frequency,
> > then we are effectively performance governor
> > (highest frequency all the time).
> Please do not confuse highest target pstate with
> highest frequency. They are not the same. The processor
> itself can back off.
Hi Doug,

All you said is about the hardware will not give whatever software wants
(e.g., requested freq too high). Agreed.

But does it matter to this discussion?

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