governor

[lucas09]

qualcuno sa le differenze dei vari governor?
perchè ho cercato un po in giro, ma non capisco diverse spiegazioni...
thanks...

[Silvereagle]

ondemand
Available in most kernels, and the default governor in most kernels. When the CPU load reaches a certain point (see "up threshold" in Advanced Settings), ondemand will rapidly scale the CPU up to meet demand, then gradually scale the CPU down when it isn't needed. - SetCPU website

conservative
Available in some kernels. It is similar to the ondemand governor, but will scale the CPU up more gradually to better fit demand. Conservative provides a less responsive experience than ondemand, but can save battery. - SetCPU website

performance
Available in most kernels. It will keep the CPU running at the "max" set value at all times. This is a bit more efficient than simply setting "max" and "min" to the same value and using ondemand because the system will not waste resources scanning for the CPU load. This governor is recommended for stable benchmarking. - SetCPU website

powersave
Available in some kernels. It will keep the CPU running at the "min" set value at all times. - SetCPU website

userspace
A method for controlling the CPU speed that isn't currently used by SetCPU. For best results, do not use the userspace governor. - SetCPU website

Interactive

The 'interactive' governor has a different approach. Instead of sampling the cpu
at a specified rate, the governor will scale the cpu frequency up when coming
out of idle. When the cpu comes out of idle, a timer is configured to fire
within 1-2 ticks. If the cpu is 100% busy from exiting idle to when the timer
fires then we assume the cpu is underpowered and ramp to MAX speed.

If the cpu was not 100% busy, then the governor evaluates the cpu load over the
last 'min_sample_rate' (default 50000 uS) to determine the cpu speed to ramp down
to.

[lucas09]

thanks....

ho trovato anche questo dove spiegato molto bene tuto quanto...
pubblico per chi fosse interessato..



SMARTASS is meant to scale the CPU frequency based on several factors such as load, battery life, screen on/off state, etc. (Note: It should not be used with setcpu profiles.)
It offers pretty good performance, although you may notice the battery draining a little faster with the screen on. (I dont mean a great amount but it's not the absolute best. With the screen off, you should get excellent battery life.)

ON-DEMAND basically is self-explanatory. Its scale is based on load. When the load is low, it keeps the frequency at the minimum. When the load hits a certain point, the frequency jumps up quickly, without stepping up much. As a result, you get better on-screen performance, but battery life isn't as good. (You'll definitely want to use profiles with this governor.)

PERFORMANCE just sets the frequency at the max defined frequency. It's primary purpose is performance testing. It saves you the trouble of raising the minimum frequency all the time. (Use it all the time if you want the best performance, but horrible battery life.)

CONSERVATIVE works just like on-demand, in that it will scale based on load, but it will not jump up and down so quickly. It will scale up in steps to save battery life. As a result, performance may not be as good, but you should get better battery life. (Used with profiles, you should get the best battery life of all the choices.)

I use smartass because it offers great performance, but also has excellent screen-off battery life (Which i need during the long hours that I am at work.)

INTERACTIVE - Similar to on-demand as well, but it reacts even quicker. Expect the same battery impact that you would get from on-demand (Better performance in exchange for slightly worse battery life).

USERSPACE - As far as I know, it does nothing. If I remember correctly, it has to do with using other apps and such to control the frequency rather than a built-in governor.

POWERSAVE - Is the opposite of performance. It holds the frequency at the minimum.

[lucas09]

sembra che smartass sia la migliore...