# Galaxy Nexus Governors Explained [All Variants][Updated]



## JamesPumaEnjoi (Jan 20, 2013)

*I DID NOT CREATE THE ORIGINAL LIST OF 20 GOVERNORS BUT I DID ADD MORE AND I DID TAKE THE TIME TO DOUBLE CHECK EACH INDIVIDUAL GOVERNOR TO MAKE SURE THEY WERE CORRECT...I MADE THIS SOLELY SO PEOPLE DONT HAVE TO GO BACK TEN PAGES TO SEE IT...a big thanks to rEcEivEr for the original thread/post I found and all the other original OP's.*

If you feel any are missing or if there are new ones I missed please let me know and we'll add them....hope this helps because I see plenty of people asking.

So let's get to it...

GOVERNORS EXPLAINED

1: OnDemand
2: OndemandX
3: Performance
4: Powersave
5: Conservative
6: Userspace
7: Min Max
8: Interactive
9: InteractiveX
10: Smartass
11: SmartassV2
12: Scary
13: Lagfree
14: Smoothass
15: Brazilianwax
16: SavagedZen
17: Lazy
18: Lionheart
19: LionheartX
20: Intellidemand
21: Hotplug
22: BadAss
23: Wheatley
24: Lulzactive
25: Pegasusq/Pegasusd
26: hotplugx
27: AbissPlug
28: MSM DCVS
29: Dyninteractive
30: Sakuractive (Thanks to Sandman-007)
31: Ktoonservative (Thanks to EniGmA1987)
32: Zen (Thanks to EniGmA1987)

1: OnDemand Governor:
This governor has a hair trigger for boosting clockspeed to the maximum speed set by the user. If the CPU load placed by the user abates, the OnDemand governor will slowly step back down through the kernel's frequency steppings until it settles at the lowest possible frequency, or the user executes another task to demand a ramp.

OnDemand has excellent interface fluidity because of its high-frequency bias, but it can also have a relatively negative effect on battery life versus other governors. OnDemand is commonly chosen by smartphone manufacturers because it is well-tested, reliable, and virtually guarantees the smoothest possible performance for the phone. This is so because users are vastly more likely to bitch about performance than they are the few hours of extra battery life another governor could have granted them.

This final fact is important to know before you read about the Interactive governor: OnDemand scales its clockspeed in a work queue context. In other words, once the task that triggered the clockspeed ramp is finished, OnDemand will attempt to move the clockspeed back to minimum. If the user executes another task that triggers OnDemand's ramp, the clockspeed will bounce from minimum to maximum. This can happen especially frequently if the user is multi-tasking. This, too, has negative implications for battery life.

2: OndemandX:
Basically an ondemand with suspend/wake profiles. This governor is supposed to be a battery friendly ondemand. When screen is off, max frequency is capped at 500 mhz. Even though ondemand is the default governor in many kernel and is considered safe/stable, the support for ondemand/ondemandX depends on CPU capability to do fast frequency switching which are very low latency frequency transitions. I have read somewhere that the performance of ondemand/ondemandx were significantly varying for different i/o schedulers. This is not true for most of the other governors. I personally feel ondemand/ondemandx goes best with SIO I/O scheduler.

3: Performance Governor:
This locks the phone's CPU at maximum frequency. While this may sound like an ugly idea, there is growing evidence to suggest that running a phone at its maximum frequency at all times will allow a faster race-to-idle. Race-to-idle is the process by which a phone completes a given task, such as syncing email, and returns the CPU to the extremely efficient low-power state. This still requires extensive testing, and a kernel that properly implements a given CPU's C-states (low power states).

4: Powersave Governor:
The opposite of the Performance governor, the Powersave governor locks the CPU frequency at the lowest frequency set by the user.

5:Conservative Governor:
This biases the phone to prefer the lowest possible clockspeed as often as possible. In other words, a larger and more persistent load must be placed on the CPU before the conservative governor will be prompted to raise the CPU clockspeed. Depending on how the developer has implemented this governor, and the minimum clockspeed chosen by the user, the conservative governor can introduce choppy performance. On the other hand, it can be good for battery life.

The Conservative Governor is also frequently described as a "slow OnDemand," if that helps to give you a more complete picture of its functionality.

6: Userspace Governor:
This governor, exceptionally rare for the world of mobile devices, allows any program executed by the user to set the CPU's operating frequency. This governor is more common amongst servers or desktop PCs where an application (like a power profile app) needs privileges to set the CPU clockspeed.

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

8: Interactive Governor:
Much like the OnDemand governor, the Interactive governor dynamically scales CPU clockspeed in response to the workload placed on the CPU by the user. This is where the similarities end. Interactive is significantly more responsive than OnDemand, because it's faster at scaling to maximum frequency.

Unlike OnDemand, which you'll recall scales clockspeed in the context of a work queue, Interactive scales the clockspeed over the course of a timer set arbitrarily by the kernel developer. In other words, if an application demands a ramp to maximum clockspeed (by placing 100% load on the CPU), a user can execute another task before the governor starts reducing CPU frequency. This can eliminate the frequency bouncing discussed in the OnDemand section. Because of this timer, Interactive is also better prepared to utilize intermediate clockspeeds that fall between the minimum and maximum CPU frequencies. This is another pro-battery life benefit of Interactive.

However, because Interactive is permitted to spend more time at maximum frequency than OnDemand (for device performance reasons), the battery-saving benefits discussed above are effectively negated. Long story short, Interactive offers better performance than OnDemand (some say the best performance of any governor) and negligibly different battery life.

Interactive also makes the assumption that a user turning the screen on will shortly be followed by the user interacting with some application on their device. Because of this, screen on triggers a ramp to maximum clockspeed, followed by the timer behavior described above.

9: InteractiveX Governor:
Created by kernel developer "Imoseyon," the InteractiveX governor is based heavily on the Interactive governor, enhanced with tuned timer parameters to better balance battery vs. performance. The InteractiveX governor's defining feature, however, is that it locks the CPU frequency to the user's lowest defined speed when the screen is off.

10: Smartass
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!"

11: SmartassV2:
Version 2 of the original smartass governor from Erasmux. Another favorite for many a people. The governor aim for an "ideal frequency", and ramp up more aggressively towards this freq and less aggressive after. It uses different ideal frequencies for screen on and screen off, namely awake_ideal_freq and sleep_ideal_freq. This governor scales down CPU very fast (to hit sleep_ideal_freq soon) while screen is off and scales up rapidly to awake_ideal_freq (500 mhz for GS2 by default) when screen is on. There's no upper limit for frequency while screen is off (unlike Smartass). So the entire frequency range is available for the governor to use during screen-on and screen-off state. The motto of this governor is a balance between performance and battery.

12: 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.

13: Lagfree:
Lagfree is similar to ondemand. Main difference is it's optimization to become more battery friendly. Frequency is gracefully decreased and increased, unlike ondemand which jumps to 100% too often. Lagfree does not skip any frequency step while scaling up or down. Remember that if there's a requirement for sudden burst of power, lagfree can not satisfy that since it has to raise cpu through each higher frequency step from current. Some users report that video playback using lagfree stutters a little.

14: Smoothass:
The same as the Smartass "governor" But MUCH more aggressive & across the board this one has a better battery life that is about a third better than stock KERNEL

15: Brazilianwax:
Similar to smartassV2. More aggressive ramping, so more performance, less battery

16: SavagedZen:
Another smartassV2 based governor. Achieves good balance between performance & battery as compared to brazilianwax.

17: Lazy:
This governor from Ezekeel is basically an ondemand with an additional parameter min_time_state to specify the minimum time CPU stays on a frequency before scaling up/down. The Idea here is to eliminate any instabilities caused by fast frequency switching by ondemand. Lazy governor polls more often than ondemand, but changes frequency only after completing min_time_state on a step overriding sampling interval. Lazy also has a screenoff_maxfreq parameter which when enabled will cause the governor to always select the maximum frequency while the screen is off.

18: Lionheart:
Lionheart is a conservative-based governor which is based on samsung's update3 source.
The tunables (such as the thresholds and sampling rate) were changed so the governor behaves more like the performance one, at the cost of battery as the scaling is very aggressive.

19: LionheartX
LionheartX is based on Lionheart but has a few changes on the tunables and features a suspend profile based on Smartass governor.

20: Intellidemand:
Intellidemand aka Intelligent Ondemand from Faux is yet another governor that's based on ondemand. Unlike what some users believe, this governor is not the replacement for OC Daemon (Having different governors for sleep and awake). The original intellidemand behaves differently according to GPU usage. When GPU is really busy (gaming, maps, benchmarking, etc) intellidemand behaves like ondemand. When GPU is 'idling' (or moderately busy), intellidemand limits max frequency to a step depending on frequencies available in your device/kernel for saving battery. This is called browsing mode. We can see some 'traces' of interactive governor here. Frequency scale-up decision is made based on idling time of CPU. Lower idling time (<20%) causes CPU to scale-up from current frequency. Frequency scale-down happens at steps=5% of max frequency. (This parameter is tunable only in conservative, among the popular governors)
To sum up, this is an intelligent ondemand that enters browsing mode to limit max frequency when GPU is idling, and (exits browsing mode) behaves like ondemand when GPU is busy; to deliver performance for gaming and such. Intellidemand does not jump to highest frequency when screen is off.

21: Hotplug Governor:
The Hotplug governor performs very similarly to the OnDemand governor, with the added benefit of being more precise about how it steps down through the kernel's frequency table as the governor measures the user's CPU load. However, the Hotplug governor's defining feature is its ability to turn unused CPU cores off during periods of low CPU utilization. This is known as "hotplugging."

22: BadAss Governor:
Badass removes all of this "fast peaking" to the max frequency. On a typical system the cpu won't go above 918Mhz and therefore stay cool and will use less power. To trigger a frequency increase, the system must run a bit @ 918Mhz with high load, then the frequency is bumped to 1188Mhz. If that is still not enough the governor gives you full throttle. (this transition should not take longer than 1-2 seconds, depending on the load your system is experiencing)
Badass will also take the gpu load into consideration. If the gpu is moderately busy it will bypass the above check and clock the cpu with 1188Mhz. If the gpu is crushed under load, badass will lift the restrictions to the cpu.

23: Wheatley:
Building on the classic 'ondemand' governor is implemented Wheatley governor. The governor has two additional parameters:

target_residency - The minimum average residency in µs which is considered acceptable for a proper efficient usage of the C4 state. Default is 10000 = 10ms.

allowed_misses - The number sampling intervals in a row the average residency is allowed to be lower than target_residency before the governor reduces the frequency. This ensures that the governor is not too aggressive in scaling down the frequency and reduces it just because some background process was temporarily causing a larger number of wakeups. The default is 5.
Wheatley works as planned and does not hinder the proper C4 usage for task where the C4 can be used properly .
For internet browsing the time spend in C4 has increased by 10% points and the average residency has increased by about 1ms. I guess these differences are mostly due to the different browsing behaviour (I spend the last time more multi-tabbing). But at least we can say that Wheatley does not interfere with the proper use of the C4 state during 'light' tasks. For music playback with screen off the time spend in C4 is practically unchanged, however the average residency is reduced from around 30ms to around 18ms, but this is still more than acceptable.

So the results show that Wheatley works as intended and ensures that the C4 state is used whenever the task allows a proper efficient usage of the C4 state. For more demanding tasks which cause a large number of wakeups and prevent the efficient usage of the C4 state, the governor resorts to the next best power saving mechanism and scales down the frequency. So with the new highly-flexible Wheatley governor one can have the best of both worlds.

Obviously, this governor is only available on multi-core devices.

24: Lulzactive:
Lulzactive:
This new find from Tegrak is based on Interactive & Smartass governors and is one of the favorites. 
Old Version: When workload is greater than or equal to 60%, the governor scales up CPU to next higher step. When workload is less than 60%, governor scales down CPU to next lower step. When screen is off, frequency is locked to global scaling minimum frequency.
New Version: Three more user configurable parameters: inc_cpu_load, pump_up_step, pump_down_step. Unlike older version, this one gives more control for the user. We can set the threshold at which governor decides to scale up/down. We can also set number of frequency steps to be skipped while polling up and down.
When workload greater than or equal to inc_cpu_load, governor scales CPU pump_up_step steps up. When workload is less than inc_cpu_load, governor scales CPU down pump_down_step steps down.
Example:
Consider
inc_cpu_load=70
pump_up_step=2
pump_down_step=1
If current frequency=200, Every up_sampling_time Us if cpu load >= 70%, cpu is scaled up 2 steps - to 800. 
If current frequency =1200, Every down_sampling_time Us if cpu load < 70%, cpu is scaled down 1 step - to 1000.

25: Pegasusq/Pegasusd

The Pegasus-q / d is a multi-core based on the Ondemand governor and governor with integrated hot-plugging.
Ongoing processes in the queue, we know that multiple processes can run simultaneously on. These processes are active in an array, which is a field called "Run Queue" queue that is ongoing, with their priority values arranged (priority will be used by the task scheduler, which then decides which process to run next).

To ensure that each process has its fair share of resources, each running for a certain period and will eventually stop and then again placed in the queue until it is your turn again. If a program is terminated, so that others can run the program with the highest priority in the current queue is executed.

26: hotplugx

It 'a Hotplug modified and optimized for the suspension in off-screen

27: AbissPlug

It 'a Governor derived hotplug, it works the same way, but with the changes in savings for a better battery.

28: MSM DCVS

a very efficient and wide range of Dynamic Clock and
Voltage Scaling (DCVS) which addresses usage models from
active standby to mid and high level processing requirements.
A Krait CPU can smoothly scale from low power, low
leakage mode to blazingly fast performance.
Believe it's a governor that is mfg'd by qualcomm to utilize new on chip features.
MSM is the prefix for the SOC (MSM8960) and DCVS is Dynamic Clock and Voltage Scaling. Makes sense, MSM-DCVS

29: Dyninterative
Similar to interactive in almost every way possible except it "dyn"amically adapts its own tunables and settings depending on system load

30: Sakuractive: This driver mimics the frequency scaling behavior in "on demand" but with several key differences. First is that frequency transitions use the CPUFreq table directly, instead of incrementing in a percentage of the maximum available frequency. Second "sakuractive" will offline auxillary CPUs when the system is idle, and online those CPUs once the system becomes busy again. This last feature is needed for architectures which transition to low power states when only the "master" CPU is online, or for thermally constrained devices

31: Ktoonservative
There is so much going on with this governor I'd rather have the makers explain it themselves....so here you go 
http://forum.xda-developers.com/showthread.php?t=2032956

32: Zen 
It's an FCFS (First come, first serve) based algorithm. It does not do any sorting. It uses deadlines for fairness, and treats synchronous requests with priority over asynchronous ones.


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## EniGmA1987 (Sep 5, 2011)

Missing a few, Ktoonservative and Zen just off the top of my head. Here is ktoonservative:

http://forum.xda-developers.com/showthread.php?t=1866139
^^^^ Although that is some old info on it. The governor has far more options now days and is IMO the most advanced governor on any Android device. It combines conservative type scaling, with interactive's boostpulse, plus has a GPU boost pulse if you so desire for extra animation smoothness, controllable boost pulse time, and hotplugging, which is also able to be disabled if you dont like to use a hotplug governor.


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## erockk13 (Sep 14, 2012)

Missin nightmare too..

Sent from my Galaxy Nexus using RootzWiki


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## tiny4579 (Oct 21, 2011)

What about interactiveX on the galaxy nexus (v2)? Its different than the one listed above. The same for intellidemand.

Sent from my Galaxy Nexus using Tapatalk 2


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## holytimes (Sep 30, 2011)

Lot of useful info I hope to see this update and be maintained. Heavens knows I have looked for this info many times.

Sent from a nexus at some point in time using a banana.


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## JamesPumaEnjoi (Jan 20, 2013)

Thanks guys....I just added Sakuractive and I'll be sure to add the ones mentioned as soon as I can confirm exactly what they are in 2 or more places....I will be updating this thread whenever possible....thanks for the feedback



holytimes said:


> Missing a few, Ktoonservative and Zen just off the top of my head. Here is ktoonservative:
> 
> http://forum.xda-developers.com/showthread.php?t=1866139
> ^^^^ Although that is some old info on it. The governor has far more options now days and is IMO the most advanced governor on any Android device. It combines conservative type scaling, with interactive's boostpulse, plus has a GPU boost pulse if you so desire for extra animation smoothness, controllable boost pulse time, and hotplugging, which is also able to be disabled if you dont like to use a hotplug governor.


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## JamesPumaEnjoi (Jan 20, 2013)

erockk13 said:


> Missin nightmare too..
> 
> Sent from my Galaxy Nexus using RootzWiki


Cannot find any info on this one right now however I'm working and not really looking very hard so I'll keep looking the next few days....all others mentioned were added


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## JamesPumaEnjoi (Jan 20, 2013)

tiny4579 said:


> What about interactiveX on the galaxy nexus (v2)? Its different than the one listed above. The same for intellidemand.
> 
> Sent from my Galaxy Nexus using Tapatalk 2


Not too sure what you mean....Imoseyeon created interactiveX and I used what his own description for it...if you have updated information on interactiveX and intellidemand please share it with me and I'll gladly add the updated info (with credit of course)


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## tiny4579 (Oct 21, 2011)

JamesPumaEnjoi said:


> Not too sure what you mean....Imoseyeon created interactiveX and I used what his own description for it...if you have updated information on interactiveX and intellidemand please share it with me and I'll gladly add the updated info (with credit of course)


he also did on the galaxy nexus but there its regular interactive plus it forces the second core offline on a screen off. Only difference from regular interactive. Also there is a screen off cap that was explictly set in his governor on the thunderbolt that wasn't added here due to the common governor screen off cap feature.

Can't answer intellidemand yet. Need to do a bit of research.

Sent from my Galaxy Nexus using Tapatalk 2


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## JamesPumaEnjoi (Jan 20, 2013)

tiny4579 said:


> he also did on the galaxy nexus but there its regular interactive plus it forces the second core offline on a screen off. Only difference from regular interactive. Also there is a screen off cap that was explictly set in his governor on the thunderbolt that wasn't added here due to the common governor screen off cap feature.
> 
> Can't answer intellidemand yet. Need to do a bit of research.
> 
> Sent from my Galaxy Nexus using Tapatalk 2


Please just share the thread or site of where you're getting the info....nothing personal....just want to do my due diligence


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## EniGmA1987 (Sep 5, 2011)

You have the info for the Zen scheduler up in the OP when you need to put the info for the Zen Governor. Kinda confusing, I know. They named the kernel, governor, and scheduler all the same thing.


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## dillanshives (Nov 23, 2011)

This post should most definitely be pinned.


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## tiny4579 (Oct 21, 2011)

@OP, regarding intellidemand. Check it out here:

http://rootzwiki.com...27/#entry282928

Scroll down to version 022 and intellidemand is described there. Also the original intellidemand governor didn't hotplug and this one does.

For interactiveX V2, check here:

http://rootzwiki.com...524#entry333524

This is also the evidence that interactiveX no longer sets a screen off maximum. Hope this helps.

Also, you weren't the first to have the older interactiveX governor description, which is correct for the phones it was originally on.


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## Trav06 (Jun 13, 2011)

JamesPumaEnjoi said:


> 9: InteractiveX Governor:
> Created by kernel developer "Imoseyon," the InteractiveX governor is based heavily on the Interactive governor, enhanced with tuned timer parameters to better balance battery vs. performance. The InteractiveX governor's defining feature, however, is that it locks the CPU frequency to the user's lowest defined speed when the screen is off.


I thought it's defining feature was hotplugging (turning off) one of the CPU cores with the screen off?


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## DR3W5K1 (Feb 19, 2012)

Trav06 said:


> I thought it's defining feature was hotplugging (turning off) one of the CPU cores with the screen off?


As far as i know this is true. Interactive also hotplugs with the screen off only if the phone is deep sleeping though. I think those are the major differences of the two from what i can tell.


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## EniGmA1987 (Sep 5, 2011)

DR3W5K1 said:


> As far as i know this is true. Interactive also hotplugs with the screen off only if the phone is deep sleeping though. I think those are the major differences of the two from what i can tell.


Does it? I thought that Interactive has no hotplugging whatsoever? Is the new hotplug feature something Google implemented or users have just all done?


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## tiny4579 (Oct 21, 2011)

EniGmA1987 said:


> Does it? I thought that Interactive has no hotplugging whatsoever? Is the new hotplug feature something Google implemented or users have just all done?


 it's true. There is deep sleep hotplugging already in the cpufreq code. Its not governor specific just like the screen off.

Sent from my Galaxy Nexus using Tapatalk 2


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