Governors/Hotplug

CPU Governors, Hotplug drivers and GPU governors (Updated 12/03/17)

My official XDA thread is here: Official XDA Thread

Recommended apps for manipulating kernel values:
1. Kernel Adiutor (Free to change governor and tune variables)
2. Kernel Adiutor-Mod (Free to change governor and tune variables)
3. Compatible kernel managers (e.g Stweaks, Synapse, UKM, etc.)

 

This pages includes:

• Descriptions
• CPU governors
• Hotplug drivers
• CPU governors
• Governor types
• Recommendations
• Graphs
• Tunables

Note to people who want to reuse this information: There have been a few websites that have included my information in their own threads. Please make sure to get appropriate credits to the original authors (including myself) that way there will be less problems! Read the policy for more information.

What is a CPU governor?

A CPU governor in Android controls how the CPU raises and lowers its frequency in response to the demands the user is placing on their device. Governors are especially important in smartphones and tablets because they have a large impact on the apparent fluidity of the interface and the battery life of the device over a charge.

NOTE: You cannot change your CPU governor unless your phone is rooted and you have a ROM or app that lets you make a change. Also, different kernels (the intermediary software between your phone's hardware and the operating system) offer different sets of governors.

Available CPU governors:

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. SavageZen
17. Lazy
18. Lionheart
19. LionheartX
20. Intellidemand
21. Hotplug
22. Badass
23. Wheatley
24. Lulzactive
25. PegasusQ\PegasusD
26. HotplugX
27. Abyssplug
28. MSM DCVS
29. Intelliactive
30. Adaptive
31. Nightmare
32. ZZmoove
33. Sleepy
34. Hyper 
35. SmartassH3
36. SLP
37. NeoX
38. ZZmanX
39. OndemandPlus
40. Dynamic Interactive (DynInteractive)
41. Smartmax
42. Ktoonservative\KtoonservativeQ
43. Performance may cry (PMC)
44. Dance Dance
45. AbyssPlugv2
46. IntelliMM
47. InteractivePro
48. Slim
49. Ondemand EPS  
50. Smartmax EPS
51. Uberdemand
52. Yankactive
53. Impulse
54. Bacon
55. Optimax
56. Preservative
57. Touchdemand
58. ElementalX
59. Bioshock
60. Blu_active
61. Umbrella_core
62. ConservativeX
63. Hyrdxq
64. DevilQ
65. Yankasusq
66. Darkness
67. Alucard
68. Hellsactive
69. Ragingmolasses
70. Virtuous
71. Sakuractive
72. InteractiveX v2
73. Alessa 
74. GallimaufryX 
75. AggressiveX
76. Tripndroid
77. Wrexy  
78. Xperience 
79. Stockdemand 
80. Zeneractive 
81. InteractiveB 
82. Aggressive 
83. IntellidemandV2 
84. Boostactive 
85. Wave 
86. Barry-Allen 
87. Arteractive 
88. Precognition (PrecoGOV) 
89. Mythx_plug 
90. PegasusQPlus 
91. Yankdemand 
92. HyperX 
93. Despair 
94. Electroactive 
95. Electrodemand 
96. Lionfish 
97. Interextrem 
98. Cafactive 
99. Lightning 
100. ThunderX 
101. sched-DVFS 
102. Intel 
103. Frankenstein
104. Cyan 
105. TheSSJactive 
106. Chill 
107. sprdemand 
108. Kraken 
109. Ironactive
     
110. Nebula
111. Relaxed

Things to look out for in a CPU governor:

There are many CPU governors available on android, but there are some important things people should look out for before selecting their new governor:

Speed 
- Some governors are faster than others and some are slower. This all depends on if the governor is biased towards performance or towards battery life. Balanced governors tend to be on the middle-ground providing optimal speed when required.  

Battery life 
- Generally, if the governor is biased towards performance, it will drain your battery faster. If the governor is biased towards battery life, the battery should drain slower. If the governor is balanced, then it will try to provide optimal performance while trying to be battery friendly when possible. This also depends on usage patterns and other factors such as background applications or wakelocks (when your CPU is on even though your screen is off). 

Stability
- The stability of a governor is dependent on a number of factors like how well the developer has implemented the governor and can vary between different devices. One governor may work well for a specific platform but may not work well on others. It is also important to look out if the governor is a Work-In-Progress (WIP) where bugs may be encountered during usage. 

Smoothness
- Not to be confused with speed, a governor can be fast but it doesn't also mean it is smooth. Some governors implement features such as touch boost to help improve the "responsiveness" when touch events are registered. Others may choose to ramp down the frequency over a timer to attempt to provide CPU power for successive events. 

Descriptions:

1: OnDemand:

Ondemand is one of the original and oldest governors available on the linux kernel.  When the load placed on your CPU reaches the set threshold, the governor will quickly ramp up to the maximum CPU frequency. It has excellent fluidity because of this high-frequency bias, but it can also have a relatively negative effect on battery life versus other governors. OnDemand was commonly chosen by smartphone manufacturers in the past because it is well-tested and reliable, but it is outdated now and is being replaced by Google's Interactive governor. 

2: OndemandX:

Basically an ondemand with suspend/wake profiles. No further optimization was done to Ondemand to keep it close to source as possible. 

3: Performance:

The performance governor locks the phone's CPU at maximum frequency. 

4: Powersave:

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

5: Conservative:

This governor 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". The original and unmodified conservative is slow and inefficient. Newer and modified versions of conservative (from some kernels) are much more responsive and are better all around for almost any use. 

6: Userspace:

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

Min Max is a governor that makes use of only min & maximum frequency based on workload. no intermediate frequencies are used! 

8: Interactive:

Interactive scales the clockspeed over the course of a timer set by the kernel developer (or user). 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. Because of this timer, Interactive is also better prepared to utilize intermediate clockspeeds that fall between the minimum and maximum CPU frequencies. It is significantly more responsive than OnDemand, because it's faster at scaling to maximum frequency.

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. 


Interactive is the default governor of choice for today's smartphone and tablet manufacturers.

9: InteractiveX:

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

Based on interactive, performance is on par with the “old” minmax and 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 it will cap it to your min frequency).

This governor will slowly ramp down frequency when the screen is off and it could also let the frequency go to low making your phone unusable (if min frequency is not checked).  


11: SmartassV2:

Version 2 of the original smartass governor from Erasmux. 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 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 up threshold, ramp up only one speed at a time, and ramp down one at a time. It will automatically cap the off screen speeds to whatever the kernel developer sets it too and will 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. 

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. Depending on the implementation, lagfree can also be performance oriented at the cost of battery life. 

14: Smoothass:

The same as the Smartass “governor” But MUCH more aggressive & across the board. 

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. 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. 

To sum up, this is an intelligent ondemand that enters browsing mode to limit max frequency when GPU is idling, and (exits browsing mode) by behaving like ondemand when GPU is busy; to deliver performance for gaming and such. Intellidemand does not jump to highest frequency when screen is off. Faux no longer recommends intellidemand and believes that intellidemand users should switch to intelliactive for better optimizations and performance. 

21: Hotplug:

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:

Badass removes all of this "fast peaking" to the max frequency. To trigger a frequency increase, the system must run a bit with high load, then the frequency is bumped. 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 to max frequency. If the gpu is crushed under load, badass will lift the restrictions to the cpu.

23: Wheatley:

This governor is build on “ondemand” but increases the C4 (the sleep state) state time of the CPU and doing so trying to save juice. 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.

Wheatley is a more performance orientated governor as it scales more aggressively than ondemand and sticks with higher frequencies. 

24:Lulzactive\LulzactiveQ:

It's based on Interactive & Smartass governors.

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.

25: Pegasusq/Pegasusd

The Pegasusq / d is a multi-core based on the Ondemand governor and governor with integrated hot-plugging. It is quite stable and has the same battery life as ondemand. 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 will run 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's a modified version of Hotplug and optimized for the suspension in off-screen

27: AbyssPlug

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

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. It makes the phone's CPU smoothly scale from low power, from low leakage mode to blazingly fast performance.Only to be used by Qualcomm CPUs.

MSM is the prefix for the SOC (MSM8960) and DCVS is Dynamic Clock and Voltage Scaling. Makes sense, MSM-DCVS

29: IntelliActive

Based off Google's Interactive governor with the following enhancements:

1. self-boost capability from input drivers (no need for PowerHAL assist)
2. two phase scheduling (idle/busy phases to prevent from jumping directly to max freq
3. Checks for offline cpus and short circuits some unnecessary checks to improve code execution paths. Therefore, it avoids CPU hotplugging. 

Created by Faux

30: Adaptive

This driver adds a dynamic cpufreq policy governor designed for latency-sensitive workloads and also for demanding performance.
This governor attempts to reduce the latency of clock so that the system is more responsive to interactive workloads in lowest steady-state but to reduce power consumption in middle operation level, level up will be done in step by step to prohibit system from going to
max operation level.

31: Nightmare 

A PegasusQ modified, less aggressive and more stable. A good compromise between performance and battery. In addition to the SoD is a prevention because it usually does not hotplug.

32: ZZmoove

The ZZmoove Governor by ZaneZam is optimized for low power consumption when the screen off, with particular attention to the limitation of consumption applications in the background with the screen off, such as listening to music. The unique feature with ZZmoove is that it has predefined profiles and allows profile switching. This governor is still a WIP as the developer is constantly giving updates! Here are the available profiles:

1. for Default (set governor defaults)
2. for Yank Battery -> old untouched setting (a very good battery/performance balanced setting DEV-NOTE: highly recommended!)
3. for Yank Battery Extreme -> old untouched setting (like yank battery but focus on battery saving)
4. for ZaneZam Battery -> old untouched setting (a more 'harsh' setting strictly focused on battery saving DEV-NOTE: might give some lags!)
5. for ZaneZam Battery Plus -> NEW! reworked 'faster' battery setting (DEV-NOTE: recommended too!  )
6. for ZaneZam Optimized -> old untouched setting (balanced setting with no focus in any direction DEV-NOTE: relict from back in the days, even though some people still like it!)
7. for ZaneZam Moderate -> NEW! setting based on 'zzopt' which has mainly (but not strictly only!) 2 cores online
8. for ZaneZam Performance -> old untouched setting (all you can get from zzmoove in terms of performance but still has the fast down scaling/hotplugging behaving)
9. for ZaneZam InZane -> NEW! based on performance with new auto fast scaling active. a new experience!
10. for ZaneZam Gaming -> NEW! based on performance with new scaling block enabled to avoid cpu overheating during gameplay
11. for ZaneZam Relax -> NEW! based on moderate (except hotplug settings) with relaxed sleep settings
    (since version 0.9 beta4: cpu temperature threshold of 65°C enabled if exynos4 cpu temperature reading support was compiled with the governor)

33: Sleepy

The Sleepy (formerly known as Solo) is an attempt to strike a balance between performance and battery power to create. It is based on Ondemand. It includes some tweaks like the Down_sampling variable and other features that set by the user through the sysfs of "echo" call. Sleepy is quite similar to Ondemandx.

34: Hyper

The Hyper (formerly known as kenobi) is an aggressive smart and smooth governor based on the Ondemand and is equipped with several features of Ondemandx suspend profiles. It also has the fast_start deep_sleep variable and detection features. In addition, the maximum frequency is in suspend mode 500Mhz or whatever the kernel devel. This is a more smoothness oriented governor which means that it is good for performance, without sacrificing much battery life.

35: SmartassH3

Based on SmartassV2 with parameters tuned by H3ROS. It has been tuned to have more efficient frequency scaling (not ramping too high when not needed) which this could potentially result in better battery life.

36: SLP 

It is a mix of pegasusq and ondemand. Therefore, it has a balance between battery savings and performance.

37: NeoX 

An optimized version of the pegasusq governor but with some extra tweaks for better performance. This means slightly more battery drainage than the original PegasusQ but it is still a balanced governor. 

38. ZZmanx

ZZmanx is exactly the same as ZZmove, but it has been renamed because DorimanX made it into his own version (possibly better performance) . However, it still suffers from below average gaming performance. (Refer to ZZmoove description for guide on profiles)

39. OnDemandPlus

Ondemandplus is an ondemand and interactive-based governor that has additional power-saving capabilities while maintaining very snappy performance. While the interactive governor provides a modern and sleek framework, the scaling logic has been been re-written completely. Reports have found that users find ondemandplus as a more battery friendly governor. In ondemandplus, the downscaling behavior from ondemand is only very slightly modified. However, the upscaling has been modified to not scale up to maximum frequency immediately.

40. Dynamic Interactive (DynInteractive)

This governor dynamically adjusts itself according to load. That means it's settings are dynamic (always changing) and not static (not changing). Dyninteractive still obtains the same great balance between battery life and performance found in the original interactive governor and improves it even further. This is not the same as the original interactive governor because of this unique behavior. 

41. Smartmax

Smartmax is a mix between ondemand and smartassv2. It behaves mostly like smartass with the concept of an "ideal" frequency. By default this is configured for battery saving, so this is NOT a gaming or benchmark governor! Additionally, to make it "snappy", smartmax has "touch poke". So input events from the touchscreen will boost the cpu for a specific time to a specific frequency. Developed by XDA user Maxwen.

42. Ktoonservative\KtoonservativeQ

Ktoonservative is based on the Conservative governor, but with the addition of new tunable variables and hotplugging. It aims to be very responsive while also being good at saving battery. This governor is highly configurable and is found in ktoonsez's kernels. 

43. Performance may cry (PMC)

A governor based on Smartmax except it's heavily tweaked for better and maximum battery life. This is not a gaming governor!

44. Dance Dance

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 is a performance focused governor but also blends with some battery savings. 

45. AbyssPlugv2

AbyssPlugv2 is a rewrite of the original CPU governor. It also fixes the problem where the governor is set only for the first core, but now governs all cores right from whatever utility you use. There have been comments on the lack of stability with this governor. 

46. IntelliMM

A rewrite of the old Min Max governor and has 3 cpu states: Idle, UI and Max. Intelliminmax (intellimm) governor is designed to work with the newer SOCs with fixed voltage rails (ie MSM8974+ SOCs). It is designed to work within those fixed voltage ranges in order to maximize battery performance while creating a smooth UI operations. It is battery friendly and spends most of the time at lower frequencies. 

47. Interactive Pro

A newer (modified) version of interactive which is optimized for devices such as the One Plus One. It is a more efficient than the original Interactive because it continuously re-evaluates the load of each CPU therefore allowing the CPU to scale efficiently.

48. Slim

A new governor from the cm branch and the slimrom project. This is a performance optimized governor and has been tuned a lot for newer devices such as the One Plus One. 

49. Ondemand EPS

A modified version of Ondemand and is optimized for newer devices. It is based on the Semaphore Kernel's Ondemand which is more optimized for battery life. The EPS at the end stands for Extreme power savings so this governor is biased to power savings!

50. Smartmax EPS

This governor is based on Smartmax but is optimized for 'Extreme Power Saving' (hence the EPS suffix). This means it uses less battery than the original Smartmax so it is not a very good gaming governor (again!) This is only found on newer devices. 

51. Uberdemand

Uberdemand is Ondemand with 2-phase feature meaning it has a soft cap at 1728 MHz so your cpu won't always go directly to max, made by Chet Kener.

52. Yankactive

A slightly modified interactive based governor by Yank555.lu. It has battery tweaks added onto it so expect better battery life! Based on user reports, this governor behaves more battery friendly than the original interactive governor without sacrificing performance. 

53. Impulse

 An improved version of interactive modified by neobuddy89. Impulse aims to have a balance between battery and performance just like interactive but has some tweaks to save battery. 

54. Bacon

This is nothing but polished interactive governor branded as "bacon" since it was adapted from bacon device thanks to neobuddy89. Most of the tweaks are for performance/latency improvements

55. Optimax governor

This is based on ONDEMAND, like almost all governors that have arisen from XDA. It contains some enhancements from LG, particularly to freq boost handling so it will boost to a set level, almost like HTC's governor. It has different tunables to the HTC governor but it behaves pretty similar, the tunables it comes with default are a bit more conservative.
It originates from Cl3kener's Uber kernel for Nexus 5, where it has quite a reputation for battery life

56. Preservative governor

This is based on the idea that the CPU will consume a lot of power when it changes frequency. It is based on the conservative governor. The idea is that it will stay at the step specified (702MHz selected by the creator Bedalus) unless needed. You will notice it will hover around 702 a lot, and not go above too much, and only to min freq when NOTHING is happening at all. This is most beneficial when you are doing something like reading; the screen is static or playing light games that won't need boosting any more
The governor comes from Moob kernel for nexus 4

57. Touchdemand

Touchdemand is based on the ondemand cpu governor but has been modified for the Tegra 3 chip (tablet only) and has additional tweaks for touchscreen responsiveness.

58. ElementalX

ElementalX is basically a multiphase Ondemand governor that aims to achieve the best balance between battery life and performance. By default, it is more conservative than Ondemand as it does not ramp up often for most phone activities. If there is a graphics load detected, the governor will switch to a two-phase Ondemand behaviour where different max frequencies are used depending on the load increase. ElementalX comes with input boost enabled by default lowering the sampling rate and increasing the frequency to improve responsiveness.

59. Bioshock

Not the game, but rather the CPU governor developed by Jamison904. A mix of ConservativeX and Lionheart. Good balance between battery savings and performance. 

60. Blu_active

A new cpu governor developed by eng.stk (featured in his Code_Blue kernels) based on interactive with upstream caf patches and ondemand governor bits too. This governor is mainly focused on performance like the other things the developer creates but it is also well balanced for gaming and general usage.

61. Umbrella_core

A new cpu governor by twisedumbrella based on interactive that is focused on battery life and not performance. It will still ramp up to a set frequency but will not stay at high frequencies for long. This governor tends to stay in high-mid range frequencies during screen_off. 

62. ConservativeX

Also developed by Imoseyon (feat. briefly in the Lean Kernel for Galaxy Nexus), the ConservativeX governor behaves like the Conservative governor with the added benefit of locking the CPU frequency to the lowest interval when the screen is off. This governor may additionally perform hotplugging on CPU1, but there is no documentation to confirm that suspicion at this time.

63. HydrxQ

Simply a lulzactiveq governor with tweaks to performance (thanks to tegrak). This means more performance and less battery life. 

64. DevilQ

An aggressive pegasusq governor which keeps the hotplugging at max 2 cpu cores to offline). This is pretty much a more optimized pegasusq for phone's with quad core processors.

65. YankasusQ

Yankasusq is another modified pegasusq but with including screen off freq tunable and some other modifications as well. The difference between PegasusQ and YanksusQ is that it doesn't ramp too aggressively when screen turns on (less battery drainage).

66. Darkness

It's based on nightmare but more simple and fast, basic configs but very complex structure. It is an updated version of the nightmare gov, so far it is quite stable in tests

67. Alucard

A favourite choice and one of the original governors that Alucard_24 made. Alucard is based on ondemand but has been heavily tweaked to bring better battery life and performance. It has been known to be battery friendly without sacrificing much performance.

68. Hellsactive

A heavily modified intelliactive governor by hellsgod that has been tweaked to improve battery life. Hellsactive is less aggressive compared to intelliactive so the battery life will be more like the original interactive. 

69. Ragingmolasses

Besides a gov with an awesome name its a mash up of conservative and ondemand and scales based on load with few tunables. Its meant to be simple, fast, and efficient at keeping the frequency away from the max clock unless it is absolutely needed. it includes gboost for better gaming.

70. Virtuous


It sets your max cpu for wake and sleep and changes the governor when your device is awake or asleep. It saves battery by lowering cpu frequencies while the device sleeps, when it awakes it automatically speeds it up again. Or alternately you can set the cpu. It is based on smartassV2(It uses 2 governors, one for sleep and other for awake)

71. Sakuractive

An aggressive hybrid of ondemand and hotplug, which means it will scale like ondemand, except a little more aggressive. But also acts like hotplug due to it shutting off a core.

72. InteractiveX v2

Also developed by Imoseyon (feat. in the Lean Kernel for Galaxy Nexus), the InteractiveX V2 governor behaves like InteractiveX, and additionally forces CPU1 into a hotplug state when the screen is off.

73. Alessa

A less aggressive and more stable ondemand modified by TeamMex. A good compromise between performance and battery. It can be used with the complementary hotplug governor. Please note that this governor is still a WIP! 

74. GallimaufryX

A modded ondemand that is a 2-stage ondemand governor with speed tweaks. It includes imoseyon's screen-off hotplugging code.

75. AggressiveX

A modded conservative governor but with lots of tweaks to increase snappiness while saving power. It also includes imoseyon's screen-off hotplugging code.

76. Tripndroid

Instead of the I/O scheduler, this is a CPU governor based on ondemand with extra tweaks for performance

77. Wrexy

Wrexy is a conservative based governor. Its similiar to the Lionheart gov. It tends to stay out of higher frequencies to favor lower frequencies but performance is not much affected. 

78. Xperience 

A tweaked smartassv2 for better performance and smoothness. Created by TeamMex. 

79. Stockdemand

A heavily modified ondemand for better performance and battery life. It is still a well balanced governor and it is designed for everyday use.

80. Zeneractive

This new "zeneractive" governor is based on interactive. It handles frequency scaling the exact same as interactive and has the same tunables as interactive for frequency scaling. However, on zeneractive all of the new hotplugging code that's in there is "from scratch." 

81. InteractiveB

An interactive based governor with a more balance battery life/performance profile

82. Aggressive

Like Lionheart, it is based on conservative, but even more aggressive

83. Intellidemandv2

Much like its predecessor, intellidemandv2 is an intelligent ondemand with browsing detection and scales based on GPU loading. It has been optimized for specific devices and has better battery life and performance. 

84. Boostactive

Based on Interactive but with cpu frequency boosting capabilities. This is performance oriented governor. 

85. Wave

Based on Conservative with some tweaks for speed and battery. This governor was created by zparallax. 

86. Barry-Allen

It's based on interactive. The governor is supposed to be more battery friendly and at the same have good performance.

87. Arteractive

It is an interactive CPU governor port from newer source code. It has more optimizations for Snapdragon 80x processors.

88. Precognition (PrecoGOV)

PrecoGOV takes over and dynamically adapts to your usage pattern. To achieve such goal, PrecoGOV manages the frequency, idle & sleep patterns, hotplugging, temperature per core and even gpu and tries to help the scheduler as best as it can, all while taking into account battery and thermal constraints.

89. Mythx_plug

It's based on an improved Interactive governor and has been modified to scale up slower and scale down faster. It is a battery friendly governor. 

90. PegasusQPlus

PegasusQPlus is a heavily tweaked PegasusQ governor, which has been implemented by AndreiLux in his Perseus kernel. PegasusQPlus should have a better balance between performance and battery usage.

91. Yankdemand

Full stock (JB) ondemand governor with changed default tunable values aimed at lower battery consumption

92. HyperX

A tweaked interactive based governor for performance.

93. Despair

It is a tweaked conservative governor with a couple extra values exposed, it tends to be a bit more conservative with battery than the conservative governor by default. Developed by DespairFactor.

94. Electroactive

The Electroactive CPU governor has been created to get some of the best balances between battery life and performance that you will see on a device. This governor is the replacement over the original electrodemand governor, being much more battery friendly with much smoother transitions compared to the original. It is a hybrid class governor, using a unique way to merge the best of both interactive and ondemand. It includes some extra additions and enhancements to be more battery saving than interactive governor and some boost tunes and additions that allow better power management and performance in games as well as better power saving when in normal use. CPU boost, graphics boost, fast_start deep_sleep and detection features are built in as well as 300 MHz clock speed in suspend. 

95. Electrodemand

Based on the ondemand cpu governor, this is the older governor that was used in the electroactive kernel which uses the same tunables found in the original ondemand governor. 

96. Lionfish

The Lionfish governor combines traits of the conservative, ondemand, and interactive governors. It is designed to maximize battery life without noticeably impacting performance. It responds quickly to heavy loads (similar to ondemand and interactive) while staying within the region of optimal CPU performance per watt. With moderate loads, it periodically votes to raise, maintain, or decrease the frequency. When there are enough votes to change the frequency, it is ramped up and down gradually. The voting mechanism reduces frequency jitter compared to ondemand and conservative. squid2's testing had found that this governor uses moderate frequencies (where efficiency is optimal) more effectively than interactive, ondemand, and conservative. This improved frequency distribution results in a moderate reduction in CPU power consumption while maintaining responsiveness comparable to the interactive governor.

97. Interextrem

A tweaked interactive governor by thehacker911. It is found in hacker kernel s6, where it has been tuned for better performance while still maintaining good battery life. 

98. Cafactive

Found in arter97's kernels, cafactive is the qualcomm optimized version of interactive from CodeAurora. This version promises to bring greatly enhanced performance over samsung's own version of interactive (benchmarks have shown a increase in performance scores), however it may be unstable on some devices and may cause some performance issues under normal and heavy operation. 

99. Lightning

Lightning is modified darkness gov made by @HridayHS

100. ThunderX

ThunderX is a power saving CPU governor based on SmartAssv2 optimized for Mediatek SoCs. 

101. sched-DVFS

A governor by Linaro and ARM that promises to provide better battery life while also being easy to configure. Unlike normal CPU governors that rely on a sampling-based approach to consider cpu time, sched-DVFS uses scheduler task utilization tracking which provides smoother scaling and better response to changing CPU load. Only found on Energy Aware Scheduling (EAS) kernels. According to some reports, energy savings differ between devices and may cause instabilities 

102. Intel

It's an interactive based governor that is optimized for Intel devices. It is thought to be more battery friendly than interactive while still having good performance. Found only on intel based SOCs.

103. Frankenstein

Based on interactive with hotplugging, it is a performance oriented governor but aims to save battery when screen is off. However, it may be unstable on some devices. Found only on intel based SOCs.

104. Cyan

Cyan is an interactive based CPU governor intended for heavy gaming and processes. It was originally developed for the i9500, but is now found in kernels for devices with intel SOCs.

105. TheSSJactive

TheSSJactive is based on yankactive but with the addition of hotplugging support for intel SOCs. It is known to be a battery friendly governor. 

106. Chill

A conservative based governor by frap129 (Electron kernel). It's aims to provide more aggressive battery savings while screen is off. 

107. sprdemand
A modded ondemand governor with functionality to offline CPUs when screen is off. It has thermal control logic implemented into the governor.

108. Kraken

Based on ElementalX but with tweaks for better performance while remaining well balanced. Found in Kraken Kernel by Team OctOS.

109. Ironactive

Based on the latest CAF 4.4 version of interactive without any additional modifications. It is found in @Tkkg1994's superkernel for the Samsung Galaxy S7.

110. Nebula

A port of the Interactive governor based on msm-4.4 sources with some mods for the HTC 10, preserving the excellent balance between performance and battery life found in many other Interactive based govs. It originated from Eliminater74's Nebula kernel and was a popular choice prior to the introduction of EAS scheduling to the kernel. 

111. Relaxed


Relaxed is based on chill, and has been altered in order to achieve more gradual frequency boosting providing battery life benefits. Relaxed uses a boost ceiling variable in order to achieve this. Rather than boosting straight to the max frequency, relaxed finds the difference between boost_counter and boost_ceiling, then boosts to max minus that difference. This governor doesn't completely replace chill, but is intended to be used alongside it. 

Hotplug drivers:

mpdecision: Qualcomm's default hotplugging driver. One of the most widely used hotplug drivers in all android devices.

msm_hotplug: Great battery life, a custom qualcomm based hotplugging driver by myflux. It is a popular choice for many users.

intelliplug: Great balance between battery life and performance. It is also a popular hotplug driver from faux123.

Alucard: A great hotplugging driver by Alucard. It is known to be very battery friendly on devices.

Kt Auto Hotplug: A great hotplug driver by Ktoonsez. Pretty much a smarter mpdecision that has been optimized for quad-core devices.

Mako Hotplug: A popular hotplug driver found in Franco kernel. Franco didn't like how closed sourced MPdecision worked and so he created this driver as a direct replacement. It always keep 2 cores online and will online additional cores based on load conditions.

Zen Decision: ZEN only onlines all cores when screen is on, it also takes thermal events into account and wont online any core back, if you're under 15% battery, or currently have a thermal event because of heat. So in the end it isn't a "real" hotplug driver, because it doesnt have any code for active hot plugging in it. That means you can't change its behavior.

Bricked Hotplug: Conservative hotplug driver by @showp1984. It is based on mpdecision but has been optimized for better balance between battery life and performance.

msm_sleeper: The main feature with this hotplug is that you can customize the screen off frequency. Two cores are always on, the third and fourth are independent and come online if needed. By default, if the load is over 80 for 400ms another core comes online. The third and/or fourth cores stay online as long as the load demands it or for a minimum of one second. While the screen is off, it goes down to a single core. Created by flar2.

Autosmp: A highly-efficient hotplug driver by @mrg666, works in-sync with the CPU governor to enable off-line cpu cores when the the CPU frequency reaches a high threshold and still more compute power is needed. Therefore, touch boost bloat is removed. 

Thunderplug: A matured load-based hotplug driver with many tunables written from ground up by varun.chitre15. This hotplug is optimized for octa-core devices and also has support for 64bit CPUs.

Blu_plug: Dynamic hotplug from eng.stk's shamu kernel with screenoff battery saving. 

cpuquiet: A hotplug driver by NVidia and ported to Snapdragon by maxwen. Originally made for NVidia tegra SOCs. It has a set of governors which keep the CPU running at optimal frequencies for battery and performance.


Fast hotplug:  A hotplug driver from pec0ra's abricot kernel. It aims to be as lightweight as possible while also being highly customizable. However, it is still a WIP as it is known to have some stability issues. 

Hima hotplug: An optimized hotplug driver based on intelliplug for big.LITTLE architecture. Found on chadouming's HTC One (M9) kernel, it takes advantage of the big and LITTLE CPU cores in order to provide 'butter smooth' performance.  

State Helper: A hotplug driver by @neobuddy89 designed with the Nexus 6 in mind. It is highly configurable giving the user control over what CPUs to online based on what battery threshold levels have been set. Another feature that sets state helper apart from other hotplug methods is that it respects the thermal driver. 

ZZmoove native hotplug: The hotplugging logic found in the ZZmoove governor. This isn't a standalone hotplug driver that can be used with other governors, the hotplugging is done by the governor which was common on older devices like the Samsung Galaxy S3. Native hotplugging may offer better stability and the governor should perform better in battery life and performance (your experience may vary) because it was designed for this specific governor.

 
Custom kernels may have their own hotplugging drivers but they are usually based on these ones. 

Battery life:

• mpdecision
• Mako Hotplug
• Intelliplug
• Alucard

For performance:

• mpdecision

For balanced:

• Bricked Hotplug
• Mako Hotplug
• Intelliplug
• mpdecision

GPU governors

Simple: An open-source alternative to Qualcomm's closed-sourced governors. Developed by Faux123, it is highly customisable which will allow more fine-grained control over how the GPU scales up and down.

simple_ondemand: As the name implies, it is a simpler version of the CPU governor ondemand. simple_ondemand will ramp up the frequency when a load is detected. It has a good balance between performance and battery savings.

msm-adreno-tz: The default GPU governor used by Qualcomm for their adreno GPUs. It is based on the ondemand governor but is biased towards performance, therefore it should give better performance in games but less battery life. 

Performance: As the name suggests, this keeps your GPU running at the max frequency. This is a governor if you want the best possible experience in games but you don't care about your battery life.


Powersave: Like the CPU governor, this keeps your GPU running at the lowest possible frequency. Best battery life, extreme lag in games.


Adreno Idler: It is an idling algorithm, an efficient workaround for msm-adreno-tz's overheads. Main goal is to lower the power consumptions while maintaining high-performance. Since msm-adreno-tz tends to *not* use the lowest frequency even on idle, Adreno idler replaces msm-adreno-tz's algorithm when it comes to calculating idle frequency(mostly by ondemand's method). The higher frequencies are not touched with this algorithm, so high-demanding games will (most likely) not suffer from worsened performance.


Userspace: This governor basically allows the user is able to set a desired frequency for the GPU to run at.


cpubw_hwmon:  A hardware monitor based governor that attempts to determine bandwidth (BW) needed by CPU and other hardware. Because it samples bandwidth using polling intervals, it has been made to be biased towards performance to compensate for the possible slower response times during heavy loads.


MSM Cpufreq: The MSM CPUfreq governor determines the CPU to DDR bandwidth vote based on the current CPU frequency of all the active CPUs. In other words, this governor scales based on CPU usage which could mean more performance.

Governor types:

All governors are coded to behave on certain principles which can affect the performance, battery life, stability of your device. I won't be updating this guide often because there is simply too many governors.

1) Ondemand Based:
Works on "ramp-up on high load" principle. CPU busy-time is taken into consideration for scaling decisions. Members: Ondemand, OndemandX, Intellidemand, Lazy, Lagfree, PegasusQ, HYPER, Wheatley, Hotplug, HotplugX, AbyssPlug, AbyssPlugv2, Nightmare, Sleepy.

2) Conservative Based:
Works by biasing the phone to prefer the lowest possible clockspeed as often as possible. Members: Conservative, Lionheart, LionheartX

3) Interactive Based:
Works on "make scaling decision when CPU comes out of idle-loop" principle. Members: Interactive, InteractiveX, Intelliactive, Lulzactive, Luzactiveq, Smartass, SmartassV2, SmartassH3, Brazilianwax, SavagedZen, Dyninteractive, Interactive Pro

4) Unique Category:
These do not fall into any other category above and/or possess unique attributes. Members: Userspace, Powersave, Performance, Min Max, ZZmove, MSM DCVS, IntelliMM

5) Hybrid Category:
These have a mix of two (or more) CPU governor behaviors. Members: Smartmax, Dancedance, Performance May Cry(PMC), Ktoonservative, KtoonservativeQ

Recommendations:

For performance:

• Interactive/InteractiveX
• Intelliactive
• Performance
• ElementalX 
• HYPER 
• Lionheart/LionheartX
• Blu_active

For battery life:

• Ondemand
• Perfomance may cry (PMC) 
• Smartmax
• Intellimm
• Alucard

For balanced battery life and performance:

• Interactive/InteractiveX
• Intelliactive 
• Ondemand/Ondemand
• ElementalX 
• Yankactive/YanksusQ 
• PegasusQ 
• HYPER 
• Impulse 
• ZZMoove

For gaming:

• Interactive/InteractiveX
• Intelliactive 
• Performance
• Lionheart/LionheartX 
• PegasusQ  
• ElementalX  
• Ondemand/OndemandX 
• HYPER

CPU governor selection on multiple cores

Some kernels will allow you to set a governor on a per-core basis. This can introduce a wider range of configurations which can alter the scaling of specific part of the CPU. While there is no definite guidelines on how to achieve optimal settings, here are some configurations you can do:

All cores running the same governor:

• This will give the best stability and the CPU will behave as expected. This is the stock default on all devices.

All cores running different governors:

• You should probably avoid this because it can cause instabilities and can significantly affect the performance and battery life of your CPU. Most kernel developers may not even provide support because there are too many combinations to choose from and because of the risks associated with this setup.

big.LITTLE cores running two different governors:

• Similar to the previous setup, this could cause instabilities on your device and could affect how well your CPU performs. It is better just to use the same governor across all cores but there have been some setups like this. 

 

Benchmark graphs:

Setup:

Phone: Samsung Galaxy S2 i9100
Governor: as per indicated
Hotplug: Default
I/O Scheduler: SIO
Kernel: DorimanX 10.44 v008 
Frequency scaling: 200-1200mhz
App: Nofrills CPU
Test procedure: Opening stock browser, navigating home screens, navigating settings screen

Link to raw data: https://drive.google.com/file/d/0B3ApZsjOd2bzWDRnQjRsUTlLSlE/view?usp=sharing

Here are more graphs (thanks to Haldi!)

(Click to zoom in)

For more info about Haldi's benchmarks, visit here: http://forum.xda-developers.com/showthread.php?t=2768979

Thanks haldi for your wonderful guide on battery savings and your graphs!

Credits go to Droidphile, Poondog, Stempox, Hipkat and many others for their descriptions. 


CPU governor tunables

NOTE: If you don't have some of these tunables, you might have an older version of the governor/hotplug driver and/or the kernel maintainer has made modifications to it.


1. ONDEMAND

[ PARAMETERS ]

Quote:

i) sampling_rate - Measured in uS , this is how often the kernel look at the CPU usage and make decisions on what to do about the frequency. Higher values means CPU polls less often. For lower frequencies, this could be considered an advantage since it might not jump to next frequency very often, but for higher frequencies, the scale-down time will be increased.

ii) up_threshold - defines what the average CPU usage between the samplings of 'sampling_rate' needs to be for the kernel to make a decision on whether it should increase the frequency.  For example when it is set to its default value of '95' it means that between the checking intervals the CPU needs to be on average more than 95% in use to then
decide that the CPU frequency needs to be increased.  

iii) powersave_bias - Default value is 0. Setting a higher value will bias the governor towards lower frequency steps. Use this if you want CPU to spend less time on higher frequencies. A better alternative would be to underclock to a lower frequency than using powersave bias.

iv) sampling_down_factor - Determines how often CPU should stay at higher frequencies when truly busy. Default behavior is fast switching to lower frequencies (1). Having sampling_down_factor set to 1 makes no changes from existing behavior (for the non-modified ondemand), but having sampling_down_factor set to a value greater than 1 causes it to act as a multiplier for the scheduling interval for re-evaluating the load when the CPU is at its highest clock frequency (which is scaling_max_freq) due to high load. T

v) down_differential - Indirectly calculates the 'down-threshold' of Ondemand. After completing sampling-down-factor*sampling-rate at max frequency because of high load, governor samples the load again to calculate an estimate of the new target frequency in a way that the lowest frequency will be chosen that would not trigger up_threshold in the next sample. Because triggering up-threshold will again cause CPU to scale up to max frequency. During this choice down_differential is taken into account as a breathing room value. Target frequency is calculated as max_load_freq / (up_threshold - down_differential).

vi) freq_step - Whenever up-scaling logic is triggered the governor instructs the CPU to raise its frequency by freq_step percentage of max allowed frequency. (max policy * (freq step / 100)). Ex: max policy is 1600 and freq step 21%, it will scale 1600 * 21% = 336.

vii) ignore_nice_load - this parameter takes a value of '0' or '1'. When set to '0' (its default), all processes are counted towards the 'cpu utilisation' value.  When set to '1', the processes that are run with a 'nice' value will not count (and thus be ignored) in the overall usage calculation.  This is useful if you are running a CPU intensive calculation on your laptop that you do not care how long it takes to complete as you can 'nice' it and prevent it from taking part in the deciding process of whether to increase your CPU frequency.

viii) sampling_rate_min - 
The sampling rate is limited by the HW transition latency:
transition_latency * 100
Or by kernel restrictions:
If CONFIG_NO_HZ is set, the limit is 10ms fixed.
If CONFIG_NO_HZ is not set or nohz=off boot parameter is used, the
limits depend on the CONFIG_HZ option:
HZ=1000: min=20000us  (20ms)
HZ=250:  min=80000us  (80ms)
HZ=100:  min=200000us (200ms)
The highest value of kernel and HW latency restrictions is shown and
used as the minimum sampling rate.

2. LULZACTIVE/LULZACTIVEQ

1. Initial Version:-

[ PARAMETERS ]

Quote:

i) down_sampling_time - Sampling time to scale cpu down.

ii) up_sampling_time - Sampling time to scale cpu up.

2. Second Version (LulzactiveQ):-

[ PARAMETERS ]

Quote:

i) inc_cpu_load - In previous version, this was 'hard-coded' to 60. Now it's user-configurable. The frequency at which governor scales CPU up/down. Load < inc_cpu_load: cpu scaled down. Load >= inc_cpu_load: cpu scaled up

ii) pump_up_step - No of scale up steps when load >= inc_cpu_load

iii) pump_down_step - No of scale down steps when load < inc_cpu_load

iv) screen_off_min_step - Steps in frequency table to be used when screen-off. Example: If available freqs are 1600 1400 1200 1000 800 500 200 100 (L0 to L7) and screen_off_min_step=5 then 100,200 and 500 (L5 to L7) will be used during screen-off depending on the demand.

v) up_sample_time - same as initial version. (Allowed values 10,000 to 50,000)

vi) down_sample_time - same as older version. (Allowed values 10,000 to 100,000)

3. SMARTASSV2

[ PARAMETERS ]

Quote:

i) awake_ideal_freq - The frequency until which CPU is scaled up rapidly on screen-awake (from sleep). Thereafter, scaling up is less aggressive.

ii) sleep_ideal_freq - The frequency until which CPU is scaled down rapidly when screen is turned off. Thereafter, scaling down is less aggressive.

iii) up_rate_us - The minimum amount of time to spend at a frequency before we can ramp up. (Ignored below awake-ideal frequency since governor needs to rapidly scale up to awake_ideal_freq when below it)

iv) down_rate_us - The minimum amount of time to spend at a frequency before we can ramp down. (Ignored above sleep-ideal frequency since governor needs to rapidly scale down to sleep_ideal_freq when above it)

v) max_cpu_load - Same as up_threshold in other governors.

vi) min_cpu_load - Same as down_threshold in other governors.

vii) ramp_down_step - Frequency delta when ramping down below the ideal frequency. Zero disables and will calculate ramp down according to load heuristic. When above the ideal frequency we always ramp down to the ideal freq.

viii) ramp_up_step - Frequency when ramping up above the ideal frequency. Zero disables and causes to always jump straight to max frequency. When below the ideal frequency we always ramp up to the ideal freq.

ix) sleep_wakeup_freq - The frequency to set when waking up from sleep. When sleep_ideal_freq=0 this will have no effect.

4. CONSERVATIVE

[ PARAMETERS ]

Quote:

Ondemand and conservative have some tunables in common, but with a few extras:

i) freq_step - this describes what percentage steps the cpu freq should be increased and decreased smoothly by.  By default the cpu frequency will increase in 5% chunks of your maximum cpu frequency.  You can change this value to anywhere between 0 and 100 where '0' will effectively lock your CPU at a speed regardless of its load whilst '100' will, in theory, make
it behave identically to the "ondemand" governor.

ii) down_threshold - same as the 'up_threshold' found for the "ondemand" governor but for the opposite direction.  For example when set to its default value of '20' it means that if the CPU usage needs to be below 20% between samples to have the frequency decreased.

5. INTERACTIVE


1. Generic Version

[ PARAMETERS ]

Quote:

i) hispeed_freq - An intermediate "hi speed" at which to initially ramp when CPU load hits the value specified in go_hispeed_load.  If load stays high for the amount of time specified in above_hispeed_delay, then speed may be bumped higher.  Default is the maximum speed allowed by the policy at governor initialization time.

ii) go_hispeed_load - The CPU load at which to ramp to hispeed_freq. Default is 99%.

iii) min_sample_time - The minimum amount of time to spend at the current frequency before ramping down. Default is 80000 uS.

iv) timer_rate - Sample rate for reevaluating CPU load when the CPU is not idle.  A deferrable timer is used, such that the CPU will not be woken from idle to service this timer until something else needs to run. (The maximum time to allow deferring this timer when not running at
minimum speed is configurable via timer_slack.)  Default is 20000 uS.

v) target_loads - CPU load values used to adjust speed to influence the current CPU load toward that value.  In general, the lower the target load, the more often the governor will raise CPU speeds to bring load below the target.  The format is a single target load, optionally followed by pairs of CPU speeds and CPU loads to target at or above those speeds.  Colons can be used between the speeds and associated target loads for readability.  For example:

   85 1000000:90 1700000:99

targets CPU load 85% below speed 1GHz, 90% at or above 1GHz, until 1.7GHz and above, at which load 99% is targeted.  If speeds are specified these must appear in ascending order.  Higher target load values are typically specified for higher speeds, that is, target load values also usually appear in an ascending order. The default is target load 90% for all speeds.

vi) above_highspeed_delay - When speed is at or above hispeed_freq, wait for this long before raising speed in response to continued high load. The format is a single delay value, optionally followed by pairs of CPU speeds and the delay to use at or above those speeds.  Colons can be used between the speeds and associated delays for readability.  For example:

   80000 1300000:200000 1500000:40000

uses delay 80000 uS until CPU speed 1.3 GHz, at which speed delay 200000 uS is used until speed 1.5 GHz, at which speed (and above) delay 40000 uS is used.  If speeds are specified these must appear in ascending order.  Default is 20000 uS.

vii) timer_slack -  Maximum additional time to defer handling the governor sampling timer beyond timer_rate when running at speeds above the minimum.  For platforms that consume additional power at idle when CPUs are running at speeds greater than minimum, this places an upper bound on how long the timer will be deferred prior to re-evaluating load and dropping speed.  For example, if timer_rate is 20000uS and timer_slack is 10000uS then timers will be deferred for up to 30msec when not at lowest speed.  A value of -1 means defer timers
indefinitely at all speeds.  Default is 80000 uS.

viii) boost - If non-zero, immediately boost speed of all CPUs to at least hispeed_freq until zero is written to this attribute.  If zero, allow CPU speeds to drop below hispeed_freq according to load as usual. Default is zero.

ix) boostpulse - On each write, immediately boost speed of all CPUs to hispeed_freq for at least the period of time specified by boostpulse_duration, after which speeds are allowed to drop below hispeed_freq according to load as usual.

x) boostpulse_duration - Length of time to hold CPU speed at hispeed_freq on a write to boostpulse, before allowing speed to drop according to load as usual.  Default is 80000 uS.

2. Qualcomm Version/Intelliactive/IntelliMM

[ PARAMETERS ]

Quote:

Has some tunables in common with the generic version but with a few extras:


i) Sync_freq Feature - This feature will cause a CPU frequency to stay above a particular
value sync_freq) if certain conditions (determined by the two nodes
up_threshold_any_cpu_freq and up_threshold_any_cpu_load) are satisfied

ii) Sync_freq - Only when both of the above conditions are satisfied will the CPU not drop
below this frequency value. The higher this value, the higher the frequency to jump will
be when the above conditions are satisfied.

iii) Up_threshold_any_cpu_freq - If the maximum frequency across all the CPUs is higher
than or equal to this frequency value, do not let the current CPU fall below sync_freq.
The higher this value, the fewer the chances to go to sync_freq.

iv) Up_threshold_any_cpu_load - If the maximum load across all the CPUs is higher than
or equal to this load value, do not let the current CPU fall below sync_freq. The higher
this value, the fewer the chances to go to sync_freq.

v) up_threshold_multi_core - When the up_threshold_multi_core is crossed, the cpu is ramped up to optimal_freq. 

vi) optimal_freq - When more than one CPU is online and if up_threshold_multi_core has exceeded, the governor will ramp up the CPU to this frequency. This value should be less than your device's max CPU frequency.

6. Wheatley

[ PARAMETERS ]

Quote:

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.

7. Darkness/Nightmare

[ PARAMETERS ]

Quote:

cpu_up_rate - No of samples to evaluate load to scale CPU frequency up. Increasing this value will increase the time spent on a frequency.

cpu_down_rate - No of samples to evaluate load to scale CPU frequency down. Increasing this value will increase the time spent on a frequency

inc_cpu_load_at_min_freq - This threshold is used as up threshold while sampling at frequencies is less than freq_for_responsiveness.

inc_cpu_load - The frequency at which governor scales CPU up.

dec_cpu_load - The frequency at which governor scales CPU down.

8. zzmoove

[ PARAMETERS ]

Quote:

sampling_rate_sleep_multiplier -> sampling rate multiplier on early suspend (possible values 1 or 2, default: 2)

up_threshold_sleep -> up threshold on early suspend (possible range from above 'down_threshold_sleep' up to 100, default: 90)

down_threshold_sleep -> down threshold on early suspend (possible range from 11 to 'under up_threshold_sleep', default: 44)

smooth_up -> smooth up scaling when screen is on (possible range from 1 to 100, default: 100)

smooth_up_sleep -> smooth up scaling on early suspend (possible range from 1 to 100, default: 100)

up_threshold_hotplug x -> hotplug threshold for cpu core x (0 disable core, possible range from 'down_threshold' up to 100, default: 68) 

down_threshold_hotplug x -> hotplug threshold for cpu core x (possible range from 1 to under 'up_threshold', default: 55)

block_down_multiplier_hotplug x -> block down multiplier for core x

block_up_multiplier_hotplug x -> block up multiplier for core x

sampling_down_max_momentum -> max sampling down factor which should be set by momentum (0 disable momentum, possible range from sampling_down_factor up to MAX_SAMPLING_DOWN_FACTOR, default 0 disabled)

sampling_down_momentum_sensitivity -> how fast the sampling down factor should be switched (possible values from 1 to 500, default 50)

sampling_down_factor -> depending on which mode is active the factor for sampling rate multiplier which influences the whole sampling rate or the value for stock 'down skip' functionality which influences only the down scaling mechanism (possible values are from 1 to MAX_SMPLING_DOWN_FACTOR, default 1 disabled)

freq_limit_sleep-> limit freqency at early suspend (possible values 0 disable limit, 200-1600, default: 0)

freq_limit -> limit freqency at awake (possible values 0 disable limit, 200-1600, default: 0)

scaling_proportional -> if enabled load-proportional frequencies will be calculated in parallel and will be used in decision for next freq step. after a comparison between normal system table step and proportional step the lowest of these two frequencies will be used for next freq step in both directions. (0 to disable, any value above 0 to enable)

scaling_block_temp -> CPU temperature threshold from where governors freq 'holding' should start. if the given temperature (if CPU temp reading is enabled) is reached the frequency used in tunable 'scaling_block_freq' will be forced targeted and scaling stays on this freq till the temperature is under the threshold again. at the same time hotplugging up work is blocked so in this throttling phase offline cores are staying offline even if the hotplug up thresholds are reached (0 to disable, values between 30 and 80 in °C)

scaling_up_block_cycles -> similar to scaling fastdown but here for a slowdown of up scaling

scaling_up_block_freq -> similar to scaling fastdown but here for a slowdown of up scaling

fast_scaling_up -> Number of scaling jumps only for upscaling when screen on (skip 0-4 frequency steps) or 5 to use autoscaling.

fast_scaling_down -> Number of scaling jumps only for downscaling when screen on (skip 0-4 frequency steps) or 5 to use autoscaling.

fast_scaling_sleep_up -> Number of scaling jumps only for upscaling when screen off (skip 0-4 frequency steps) or 5 to use autoscaling.

fast_scaling_sleep_down -> Number of scaling jumps only for downscaling when screen off (skip 0-4 frequency steps) or 5 to use autoscaling.

disable_hotplug -> switch to enable/disable hotplugging (possible values are any value above 0 to disable hotplugging and 0 to enable it, default 0)

auto_adjust_freq_thresholds -> if enabled all freq thresholds used by the governor will be adjusted accordingly to the new scaling max policy. in particular the thresholds will be increased/decreased by the actual changed max freq step if that change will undercut/exceed the actual min/max freq policy it will stop at the max possible frequency step before undercutting/exceeding min/max freq policy (0 to disable, any value above 0 to enable)

early_demand -> switch to enable/disable early demand functionality (possible values 0 disable or 1 enable, default: 0)

grad_up_threshold -> scale up frequency if the load goes up in one step of grad up value (possible range from 1 to 100, default 50) little example for understanding: when the load rises up in one big 50% step then the frequency will be scaled up immediately instead of wating till up_threshold is reached.

early_demand_sleep -> same function as early demand on awake but in addition combined with fast scaling and sampling rate switch and only active at sleep. (possible values 0 disable or 1 enable, default is 1)

grad_up_threshold_sleep -> 2 way functionality: early demand sleep grad up (load gradient) threshold and at the same time load threshold for switching internally (tuneables are staying at set values!) sampling_rate_sleep_multiplier to 2 and fast_scaling to 2 (possible values from 1 to 100, default is 35)

hotplug_block_up_cycles -> (replaces hotplug_block_cycles) slow down up hotplugging by waiting a given amount of cycles before plugging. possible values 0 disable, any values above 0 (default is 0)

hotplug_block_down_cycles -> (replaces hotplug_block_cycles) slow down down hotplugging by waiting a given amount of cycles before plugging. possible values 0 disbale, any values above 0 (default is 0)

hotplug_idle_freq -> freq at which the idle should be active (possible values 0 disable and any possible scaling freq, default is 0)

sampling_rate_current -> read only and shows currently active sampling rate

sampling_rate_idle -> sampling rate which should be used at 'idle times' (possible values are any sampling rate > 'min_sampling_rate', 0 to disable whole function, default is 0)

sampling_rate_idle_delay -> delay in cycles for switching from idle to normal sampling rate and vice versa (possible values are any value and 0 to disable delay, default is 0)

sampling_rate_idle_threshold -> threshold under which idle sampling rate should be active (possible values 1 to 100, 0 to disable function, default is 0)

scaling_block_cycles -> amount of gradients which should be counted (if block threshold is set) and at the same time up scaling should be blocked and after that a forced down scaling should happen (possible values are any value, 0 to disable that function, default is 0)

scaling_block_freq -> frequency at and above the blocking should be active (possible values are any possible scaling freq, 0 to enable blocking permanently at every frequency, default is 0)

scaling_block_threshold -> gradient (min value) of load in both directions (up/down) to count-up cycles (possible value are 1 to 100, 0 to disable gradient counting)

scaling_block_force_down -> multiplier for the maximal amount of forced down scaling cycles (force down cycles = block_cycles * force_down) therefore the forced down scaling duration (possible value are 2 to any value, 0 to disable forced down scaling and use only scaling up blocks)

profile_number -> switches profile (possible value depends on amount of profiles in cpufreq_zzmoove_profiles.h file, please check this file for further details!) 0 = tunable mode, default 0)

scaling_fastdown_freq -> will be enabled once this frequency has been met or exceeded (0 to disable, all possible system frequencies, default is 0)

scaling_fastdown_up_threshold -> once the above frequency threshold has been met, this will become the new up_threshold until we fall below the scaling_fastdown_freq again. (range from over fastdown_down_threshold to 100, default is 95)

scaling_fastdown_down_threshold -> once the above frequency threshold has been met, this will become the new down_threshold until we fall below the scaling_fastdown_freq again. (range from 11 to under fastdown_up_threshold, default is 90)

scaling_responsiveness_freq -> will be enabled once this frequency has been met or exceeded (0 to disable, all possible system frequencies, default is 0)

scaling_responsiveness_up_threshold -> the up_threshold that will take effect if scaling_responsiveness_freq is set (range from 11 to 100, default is 30)

hotplug_engage_freq -> will not bring any cores online until this frequency is met or exceeded
(0 to disable, all possible system frequencies, default is 0)

music_max_freq -> maximum frequency for CPU when governor is on music mode

music_min_cores -> minimum CPU cores used when governor is on music mode

music_min_freq -> minimum frequency for CPU when governor is on music mode

afs_threshold 1,2,3 -> Auto fast scaling for step one to three respectively (range from 1 to 100)

9. Smartmax/Performance May Cry

[ PARAMETERS ]

Quote:

boost_duration - how long you want the governor to boost your CPU in seconds.

down_rate - The minimum amount of time in nsecs to spend at a frequency before we can ramp down. Notice we ignore this when we are above the ideal frequency.

io_is_busy - Consider if IO is busy

max_cpu_load - CPU freq will be increased if measured load > max_cpu_load

min_cpu_load - CPU freq will be decreased if measured load < min_cpu_load

ramp_up_during_boost - should ramp_up steps during boost be possible

ramp_up_step - Frequency delta when ramping up above the ideal frequency. Zero disables and causes to always jump straight to max frequency. When below the ideal freqeuncy we always ramp up to the ideal freq.

Touch_poke_freq - Also known as the touch boost frequency. This is the frequency that you CPU jumps to when touching screen.

Hotplug tunables

Mako Hotplug:

Quote:

load_threshold: system load threshold to decide when online or offline cores from 0 to 100

high_load_counter: counter to filter online/offline calls. The load needs to be above load_threshold X high_load_counter times for the cores to go online otherwise they stay offline

max_load_counter: max number of samples counters allowed to be counted. The higher thevalue the longer it will take the driver to offline cores after a period of high and continuous load

cpufreq_unplug_limit: if the current CPU freq is above this limit don't offline the cores for a couple of extra samples

min_time_cpu_online: minimum time in seconds that a core stays online to avoid too many online/offline calls

int timer: sample timer in seconds. The default value of 1 equals to 10 samples every second. The higher the value the less samples per second it runs

msm_mpdecision/bricked hotplug

Quote:

startdelay = time until mpdecision starts doing it's magic (20000)

delay = time between checks (70)

pause = if something else plugs in the cpu, fall asleep for 10000ms (10 secs)

scroff_single_core = if the screen is off, don't plug in cpu1/2/3. Additionally: Unplug all cpus except cpu0 when screen is turned off (1)

enabled = enable(1) or disable(0) mpdecision. This does not affect scroff_single_core!

min_cpus = min cpus to be online, cannot be < 1.

max_cpus = max cpus to be online (if you set it to 2 and min_cpus to 1 you will basically have a dualcore)

idle_freq = a value against that will be checked if a core +/- is requested.

nwns_threshold_x = runqueue threshold, if this is reached cpuX will be hot/unplugged

twts_threshold_x = time threshold, this amount of time must have passed for the related action to be taken (hot/unplug)

AutoSMP

Quote:

max_cpus, min_cpus, scroff_single_core, delay: Look at description above

enabled: Enable/Disable AutoSMP. Y ( for enabled). N (for disabled)

cpufreq_down: Percentage values for downrate limit (range from 0 - 100)

cpufreq_up: Percentage values for uprate limits (range from 0 - 100)

cycle_down: Cycles to wait after the last hotplug event to unplug another core (values 0 1 2 3 4)

cycle_up: Cycles to wait after the last hotplug event to plug another core (values 0 1 2 3 4)

Alucard

(sourced from defconoi's kernel guide)

Quote:

hotplug_sampling_rate:
Sampling Interval, measured in ms. This factor determines how often the governor should poll for CPU usage in terms of frequency and load percentage to make hotplugging decisions. (Default: 30 ms)

hotplug_rate_1_1:
Number of samples to evaluate cpu1 hotplug in. (Default: 1)

hotplug_rate_2_0:
Number of samples to evaluate cpu1 hotplug out. (Default: 5)

hotplug_rate_2_1:
Number of samples to evaluate cpu2 hotplug in. (Default: 2)

hotplug_rate_3_0:
Number of samples to evaluate cpu2 hotplug out. (Default: 5)

hotplug_rate_3_1:
Number of samples to evaluate cpu3 hotplug in. (Default: 2)

hotplug_rate_4_0:
Number of samples to evaluate cpu3 hotplug out. (Default: 5)

hotplug_freq_1_1:
Up threshold frequency to turn second core On, when some other conditions is also met. ie If (minimum frequency greater than or equal to hotplug_freq 1 1) Hotplug IN Second Core. Higher value corresponds to delay in turning on second core. 

hotplug_freq_2_0:
Down threshold frequency to turn second core Off, when some other conditions is also met. ie If (maximum frequency less than hotplug_freq 2 0) Hotplug OUT Second Core. Lower value corresponds to delay in turning off second core.

hotplug_freq_2_1:
Up threshold frequency to turn third core On, when some other conditions is also met. ie If (minimum frequency greater than or equal to hotplug_freq 2 1) Hotplug IN Third Core. Higher value corresponds to delay in turning on Third core. 

hotplug_freq_3_0:
Down threshold frequency to turn third core Off, when some other conditions is also met. ie If (maximum frequency less than hotplug_freq 3 0) Hotplug OUT Third Core. Lower value corresponds to delay in turning off third core. 

hotplug_freq_3_1:
Up threshold frequency to turn fourth core On, when some other conditions is also met. ie If (minimum frequency greater than or equal to hotplug_freq 3 1) Hotplug IN Fourth Core. Higher value corresponds to delay in turning on Fourth core. 

hotplug_freq_4_0:
Down threshold frequency to turn fourth core Off, when some other conditions is also met. ie If (maximum frequency less than hotplug_freq 4 0) Hotplug OUT Fourth Core. Lower value corresponds to delay in turning off fourth core. 

hotplug_load_1_1:
The CPU load at which governor scales CPU up. Current Load equal or greater than up_load: CPU Hotplug IN. Value corresponding to 101 causes not HOTPLUG IN. (Default: 60%)

hotplug_load_2_0:
The CPU load at which governor scales CPU down. Current Load less than down_load and CPU online greater than 1: CPU Hotplug OUT. Value corresponding to 101 causes immediately HOTPLUG OUT. (Default: 30%)

hotplug_load_2_1:
The CPU load at which governor scales CPU up. Current Load equal or greater than up_load: CPU Hotplug IN. Value corresponding to 101 causes not HOTPLUG IN. (Default: 65%)

hotplug_load_3_0:
The CPU load at which governor scales CPU down. Current Load less than down_load and CPU online greater than 1: CPU Hotplug OUT. Value corresponding to 101 causes immediately HOTPLUG OUT. (Default: 30%)

hotplug_load_3_1:
The CPU load at which governor scales CPU up. Current Load equal or greater than up_load: CPU Hotplug IN. Value corresponding to 101 causes not HOTPLUG IN. (Default: 65%)

hotplug_load_4_0:
The CPU load at which governor scales CPU down. Current Load less than down_load and CPU online greater than 1: CPU Hotplug OUT. Value corresponding to 101 causes immediately HOTPLUG OUT. (Default: 20%)

hotplug_rq_1_1:
Threshold run queue length for second core to turn on. (Default: 100)

hotplug_rq_2_0:
Threshold run queue length for second core to turn off. (Default: 100)

hotplug_rq_2_1:
Threshold run queue length for third core to turn on. (Default: 200)

hotplug_rq_3_0:
Threshold run queue length for third core to turn off. (Default: 200)

hotplug_rq_3_1:
Threshold run queue length for fourth core to turn on. (Default: 300)

hotplug_rq_4_0:
Threshold run queue length for fourth core to turn off. (Default: 300)

maxcoreslimit:
Max CPU's hotplugging limit. (Default: 4)

maxcoreslimit_sleep:
Max CPU's hotplugging limit. (Default: 2)

Source: xda-developers, android open source generic linux kernel documentation