[XPERIA X10 General] chiefy009:
I wanted to know what the different governors do, rather than filling dev's threads up with questions I thought i would have a look around and do this for others who like me wanted to know what they do:

1: Interactive

The CPUfreq governor "interactive" is designed for low latency, interactive workloads. This governor sets the CPU speed depending on usage, similar to "ondemand" and "conservative" governors. However there is no polling, or 'sample_rate' required to scale the CPU up. Sampling CPU load every X ms can lead to under powering the CPU for X ms, leading to dropped framerate, stuttering UI etc..Scaling the CPU up is done when coming out of idle, and like "ondemand" scaling up will always go to MAX, then step down based off of cpu load.

There is only one tuneable value for this governor: min_sample_time: The ammount of time the CPU must spend (in uS) at the current frequency before scaling DOWN. This is done to

more accurately determine the cpu workload and the best speed for that workload. The default is 50ms.

2:Min Max

well this governor makes use of only min & maximum frequency based on workload... no intermediate frequencies are used.

3:Smartass

(Quoted from another author http://www.ziggy471.com/2010/11/07/s...-governor-info ) - "is based on the concept of the interactive governor.

I have always agreed that in theory the way interactive works – by taking over the idle loop – is very attractive. I have never managed to tweak it so it would behave decently in real life. Smartass is a complete rewrite of the code plus more. I think its a success. Performance is on par with the “old” minmax and I think smartass is a bit more responsive. Battery life is hard to quantify precisely but it does spend much more time at the lower frequencies.

Smartass will also cap the max frequency when sleeping to 352Mhz (or if your min frequency is higher than 352 – why?! – it will cap it to your min frequency). Lets take for example the 528/176 kernel, it will sleep at 352/176. No need for sleep profiles any more!"

4:Scary

A new governor wrote based on conservative with some smartass features, it scales accordingly to conservatives laws. So it will start from the bottom, take a load sample, if it's above the upthreshold, ramp up only one speed at a time, and ramp down one at a time. It will automatically cap the off screen speeds to 245Mhz, and if your min freq is higher than 245mhz, it will reset the min to 120mhz while screen is off and restore it upon screen awakening, and still scale accordingly to conservatives laws. So it spends most of its time at lower frequencies. The goal of this is to get the best battery life with decent performance. It will give the same performance as conservative right now, it will get tweaked over time.

I assume performance, conservative, powersave and ondemand are self explanatory,

Userspace - finding conflicting info, so if a dev wants to help me out ??

All this info was found on the web in various places, where possible I have quoted where from. If people would like me to link back to them please let me know I will add.

This is purely to help people understand the governors a little without filling dev threads

Can people also leave user feedback on the governors they have been using to give us a reference point to help us all

if it helped hit thanks

Dooms Kernel : http://xdaforums.com/showthread.php?t=1226826

Schedulers post 3