CPU Governors, Hotplug drivers and GPU governors Explained Part 1 (Updated 23/12/16)
------------------------------------------------------------------------------------------------------------------
Official XDA thread Of The Contributer: http://forum.xda-developers.com/member.php?u=5811506
Edited By ShivaY: http://forum.xda-developers.com/member.php?u=6704044
Guide Part 2 Link: http://forum.xda-developers.com/lenovo-a6000/how-to/cpu-governors-hotplug-drivers-gpu-t3528766
Guide Part 3 Link :http://forum.xda-developers.com/lenovo-a6000/how-to/cpu-governors-hotplug-drivers-gpu-t3528771
Guide Part 4 Link : http://forum.xda-developers.com/lenovo-a6000/how-to/cpu-governors-hotplug-drivers-gpu-t3528772
Here I've gathered some info for newcomers to the Android world.I've tried to keep it relatively simple. So if you want more info Comment Below
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
governors
Hotplug drivers
CPU governors
Governor types
Recommendations
Graphs
Tunables
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
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
Guide Part 2 Link: http://forum.xda-developers.com/lenovo-a6000/how-to/cpu-governors-hotplug-drivers-gpu-t3528766
Guide Part 3 Link :http://forum.xda-developers.com/lenovo-a6000/how-to/cpu-governors-hotplug-drivers-gpu-t3528771
Guide Part 4 Link : http://forum.xda-developers.com/lenovo-a6000/how-to/cpu-governors-hotplug-drivers-gpu-t3528772
Please Press Thanks Button If It Helped . It Will Encourage Me to Work More For You Guys
THANK YOU:good:
Related
Thanks to deedii for posting this in another forum:
http://forum.xda-developers.com/show...65&postcount=2
Android CPU 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
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 ***** 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.
Credits goes to:
http://icrontic.com/discussion/95140...m-tuner-tegrak
http://forum.xda-developers.com/show....php?t=1369817
Thank you for the great information.
Cool its interesting to know all the features of the govs I used thx
Sent from my LG-P500 using xda premium
updated
I've been reading the forums for a while, and i sometimes come across something like OC governor. What do "governor" mean? Is it like preset settings? Thank you for the help!
atishpatel2012 said:
I've been reading the forums for a while, and i sometimes come across something like OC governor. What do "governor" mean? Is it like preset settings? Thank you for the help!
Click to expand...
Click to collapse
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
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 ***** 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."
Kanged from here: http://androidforums.com/xperia-mini-all-things-root/513426-android-cpu-governors-explained.html
Great post thanks very usefull:thumbup:
Sent from my HTC6435LVW using xda app-developers app
Android CPU governors and schedulers explained in easy to understand language.
What is a governor?
A governor is a driver for the regulation of CPUFreq - CPU frequency. As the name suggests, we, the Governor of the decision, when at full capacity, the MaxFreq - will be achieved or how fast the minFreq - - maximum frequency is reached minimum frequency or center frequency. He decides when, how and how long the CPU and still responds battery saving is still soft and still works.
There are many types of governors. Some are for single-core processors and some designed for dual-core processors. In stock kernel, there are five governors and quasar kernel, there are a lot more.
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: Wheatley
23: Lulzactive
24: AbyssPlug
25. BadAss
26. Ktoonservative
27. AssWax
28. Sleepy
29. Hyper
30: Pegasusq/Pegasusd
31: MSM DCVS
32: hotplugx
33: zen
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 ***** 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 scales CPU frequency based on load, similar to “ondemand”. It scales up to the highest frequency when “up_threshold” is crossed and scales down one frequency at a time when “down_threshold” is crossed. Unlike those governors, target frequencies are determined by directly accessing the CPUfreq frequency table, instead of taking some percentage of maximum available frequency.
The key difference in the “hotplug” governor is that it will disable auxillary CPUs when the system is very idle, and enable them again once the system becomes busy. This is achieved by averaging load over multiple sampling periods; if CPUs were online or offlined based on a single sampling period then thrashing will occur.
Sysfs entries exist for “hotplug_in_sampling_periods” and for “hotplug_out_sampling_periods” which determine how many consecutive periods get averaged to determine if auxillery CPUs should be onlined or offlined. Defaults are 5 periods and 20 periods respectively. Otherwise the standard sysfs entries you might find for “ondemand” and “conservative” governors are there.
Obviously, this governor is only available on multi-core devices.
22: Wheatley
in short words this govenor is build on “ondemand” but increases the C4 state time of the CPU and doing so trying to save juice.
23: Basically interactive governor with added smartass bits and variable (as opposed to fixed amout) frequency scaling, based on currently occuring cpu loads. Has, like smartass, a sleep profile built-in. See link for details on exact scaling.
24: Abyssplug governor is a modified hotplug governor.
25. 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.
26, Ktonnservative
Ondemand scales to the highest frequency as soon as a load occurs. Conservative scales upward based on the frequency step variable which means for the most part will scale through every frequency to achieve the target load thresholds. What this practically means is ondemand is prone to wasting power on unneeded clock cycles. Ondemand also features something called a down differential, this variable determines how long the governor will remain at the given frequency before scaling down. Conservative does not have this, but instead relies on having a down threshold which insures that as soon as the load drops below a given variable it scales down as fast as the sampling rate allows. The result to this is a governor which attempts to keep the load level tolerable and save you battery! Now ! Ktoonservative Is that but in addition contains a hotpluging variable which determines when the second core comes online. The governor shuts the core off when it returns to the second lowest frequency thus giving us a handle on the second performance factor in our CPUs behavior. While by default conservative is a poor performer it can be made to perform comparably to even performance governor. Here are some settings to discuss and start with. They are slightly less battery friendly under a load but very very well performing.
27. AssWax
So far, all I have found about this Governor is that it belongs in the interactive family. I'll update this when I find more
28. 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 the getweakten Ondemand of Arighi and is optimized for the SGS2. It may include imoseyon's Ondemandx with some tweaks Down_sampling and other features that set by the user through the sysfs of "echo" call. Sleepy is the behavior of Ondemandx when he is in action, very similar.
29. Hyper
The Hyper (formerly known as kenobi) is an aggressive smart and smooth, optimized for SGS2 getweakt and, based on the Ondemand, which was getweakt of Arighi and was equipped with several features of Ondemandx suspend imoseyon. (Added by sysfs, the settings suspend_freq and suspend Imoseyon's code) is the behavior of the hyper Ondemand if he is in action, very similar. He also has the Arighi's fast_start deep_sleep and detection features. In addition, the maximum frequency is in suspend mode 500Mhz.
30: 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.
31: 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
32: hotplugx
It 'a Hotplug modified and optimized for the suspension in off-screen
33: zen
It's an FCFS (First come, first serve) based algorithm. It's not strictly FIFO. It does not do any sorting. It uses deadlines for fairness, and treats synchronous requests with priority over asynchronous ones. Other than that, pretty much the same as no-op.
What is a scheduler?
In a multitasking operating system, there must be an instance, the processes that want to run, CPU time and allocates it "goes to sleep" after the allotted time (timeslice) again. This instance is called the scheduler, such as opening and closing applications. that is, how fast they are open and how long they are kept in RAM.
I / O scheduler can have many purposes like:
To minimize time searching on the hard disk
Set priorities for specific process requests
To regulate a particular portion of the bandwidth of the data carrier to each running process
To guarantee certain process requests within a certain time
Which scheduler are available?
CFQ
Deadline
VR
Simple
Noop
Anticipatory
BFQ
Sio
Anticipatory:
Two important things here are indicative of that event:
- Looking on the flash drive is very slow from Equip
- Write operations while at any time are processed, however, be read operations preferred, ie, this scheduler returns the read operations a higher priority than the write operations.
Benefits:
- Requests of read accesses are never treated secondarily, that has equally good reading performance on flash drives like the noop
Disadvantages:
- Requests from process operations are not always available
- Reduced write performance on high-performance hard drives
CFQ:
The CFQ - Completely Fair Queuing - similar to the Dead Line maintains a scalable continuous Prozess-I/O-Warteschlange, ie the available I / O bandwidth tried fairly and evenly to all I / O requests to distribute. He created a statistics between blocks and processes. With these statistics it can "guess" when the next block is requested by what process, ie each process queue contains requests of synchronous processes, which in turn is dependent upon the priority of the original process. There is a V2 and the CFQ has some fixes, such as were the I / O request, hunger, and some small search backward integrated to improve the responsiveness.
Benefits:
- Has the goal of a balanced I / O performance to deliver
- The easiest way to set
- Excellent on multiprocessor systems
- Best performance of the database after the deadline
Disadvantages:
- Some reported user that the media scanning would take this very very long time and this by the very fair and even distribution of bandwidth on the I / O operations during the boot process is conditioned with the media scanning is not necessarily the highest should have priority
- Jitter (worst case delay) can sometimes be very high because the number of competing with each other process tasks
Deadline:
This scheduler has the goal of reducing I / O wait time of a process of inquiry. This is done using the block numbers of the data on the drive. This also blocks an outlying block numbers are processed, each request receives a maximum delivery time. This is in addition to the Governor BFQ very popular and in many well known kernels, such as the Nexus S Netarchy. He was indeed better than the BFQ, but compared to the VR he will be weaker.
Benefits:
- Is nearly a real-time scheduler.
- Characterized by reducing the waiting time of each process from - best scheduler for database access and queries.
- Bandwidth requirements of a process, eg what percentage does a CPU is easy to calculate.
- As the Governor-noop ideal for flash drives
Disadvantages:
- If the system is overloaded, can go a lost set of processes, and is not as easy to predict
SIO:
It aims to achieve with minimal effort at a low latency I / O requests. Not a priority to put in queue, instead simply merge the requests. This scheduler is a mix between the noop and deadline. With him there is no conversion or sorting of requests.
Benefits:
- It is simple and stable. - Minimized Starvations (starvation) for inquiries
Disadvantages:
- Slow random write speeds on flash drives as opposed to other schedulers. - Sequential read speeds on flash drives, not as good
Noop:
The noop scheduler is the simplest of them. He is best suited for storage devices that are not subject to mechanical movements, such as our flash drives in our SGSII's to use to access the data. The advantage is that flash drives do not require rearrangement of the I / O requests, unlike normal hard drives. ie the data that come first are written first. He's basically not a real scheduler, as it leaves the scheduling of the hardware.
Benefits:
- Adds all incoming I / O requests in a first-come-who-first-served queue and implements requests with the fewest number of CPU cycles, so also battery friendly
- Is suitable for flash drives because there is no search errors
- Good data throughput on db systems
Disadvantages:
- Reducing the number of CPU cycles corresponds to a simultaneous decline in performance einhergehendem
VR:
Unlike other scheduling software, synchronous and asynchronous requests are not handled separately, but it will impose a fair and balanced within this deadline requests, that the next request to be served is a function of distance from the last request. The VR is a very good scheduler with elements of the deadline scheduler. He will probably be the best for MTD Android devices. He is the one who can make the most of the benchmark points, but he is also an unstable schedulers, because his performance falter. Sometimes they fluctuate below the average, sometimes it fluctuates above the average, but if above, then he is the best.
Benefits:
- Is the best scheduler for benchmarks
Disadvantages:
- Performance variability can lead to different results
- Very often unstable or unzverlässig
Simple:
As the name suggests, it is more of a simple or simple scheduler. Especially suitable for EMMC devices. He is reliable, maybe not as good as the VR, when this time has a good day, but he is despite all this very performance-based and does his best. At the moment it is the default scheduler in quasar kernel.
Advantages: - not known
Cons: - not known
BFQ:
Instead requests divided into time segments as the CFQ has, on the BFQ budget. The flash drive will be granted an active process until it has exhausted its budget (number of sectors on the flash drive). The awards BFQ high budget does not read tasks.
Benefits:
- Has a very good USB data transfer rate.
- Be the best scheduler for playback of HD video recording and video streaming (due to less jitter than CFQ Scheduler, and others)
- Regarded as a very precise working Scheduler
- Delivers 30% more throughput than CFQ
Disadvantages:
- Not the best scheduler for benchmarks - higher budgets that were allocated to a process that can affect the interactivity and bring with it increased latency.
How can I change the governor and scheduler?
There are two ways to change the governor and schedulers, as well as the settings for the Governorn. Either manually, in which you use a file manager like Root Explorer and then knows how to / sys / devices / system and then change the files to his wishes, provided you what you're doing, or via a graphical interface or by phone as SetCPU Voltage Control. These are the most prominent apps when it comes to adjusting the governor and / or scheduler.
- SetCPU are, besides the possibility of the clock speed of the CPU, setting profiles in certain situations, only to change the way the governor. The scheduler can not change it.
- Voltage control can alter both the governor and the scheduler, but has no way to adjust behavior profiles. While you can set various overclocking, Governor and scheduler profiles manually, but nothing more. Nevertheless, I prefer the VC, since it is simple and gives me the opportunity to change the scheduler.
If you find any other IMPORTANT governors being left out , just leave a comment.
Credit goes to jpkelly05 , stempox and XDA
reserved
Good Job!!
Informative thread!!
Must be made a sticky I guess.
Good Job man really helps a lot in deciding which governor i should use! but i think u forgot smaartassH3
Ace King 34 said:
Good Job!!
Informative thread!!
Must be made a sticky I guess.
Click to expand...
Click to collapse
yeah i guess :highfive: :good:
Blackbox421 said:
Good Job man really helps a lot in deciding which governor i should use! but i think u forgot smaartassH3
Click to expand...
Click to collapse
i thought its not used that much . . . anyways ill add it soon
CPU Governors, Hotplug drivers and GPU governors Explained Part 1 (Updated 30/12/16)
------------------------------------------------------------------------------------------------------------------
Official XDA thread Of The Contributer: http://forum.xda-developers.com/member.php?u=5811506
Edited By ShivaY: http://forum.xda-developers.com/member.php?u=6704044
Guide Part 2 Link: http://forum.xda-developers.com/lenovo-a6000/how-to/cpu-governors-hotplug-drivers-gpu-t3528766
Guide Part 3 Link :http://forum.xda-developers.com/lenovo-a6000/how-to/cpu-governors-hotplug-drivers-gpu-t3528771
Guide Part 4 Link : http://forum.xda-developers.com/lenovo-a6000/how-to/cpu-governors-hotplug-drivers-gpu-t3528772
Here I've gathered some info for newcomers to the Android world.I've tried to keep it relatively simple. So if you want more info Comment Below
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
governors
Hotplug drivers
CPU governors
Governor types
Recommendations
Graphs
Tunables
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
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
Guide Part 2 Link: http://forum.xda-developers.com/lenovo-a6000/how-to/cpu-governors-hotplug-drivers-gpu-t3528766
Guide Part 3 Link :http://forum.xda-developers.com/lenovo-a6000/how-to/cpu-governors-hotplug-drivers-gpu-t3528771
Guide Part 4 Link : http://forum.xda-developers.com/lenovo-a6000/how-to/cpu-governors-hotplug-drivers-gpu-t3528772
Please Press Thanks Button If It Helped . It Will Encourage Me to Work More For You Guys
THANK YOU:good:
Blu
Holy crap man....! This is a long guide. I really appreciate this guide & it helped me a lot to learn. You're awesome... I wish you to be able to do more like this. Thanks & cheers..... ???????
Hi there. So I have used my mido for two years now and experimented with a lot of things to achieve optimal performance and speed, balance. However as much as I wanted to know moré about GPU governors the guides online are way too superficial. Not to mention most of them are outdated.
Could somebody, like anyone who knows a bit about them help me understand their differences and uses?
These are the most common governors that are almost always present in custom kernels:
spdm_bw_hyp
bw_hwmon
venus-ddr-gov
msm-vidc-vmem
msm-vidc-vmem+
msm-vidc-ddr
bw_vbif
gpubw_mon
msm_adreno_tz
cpufreq
userspace
simple_ondemand
powersave
performance
Msm_adreno_tz, cpufreq, cpufreq, userspace, simple_ondemand, powersave and performance are the ones that I could figure out myself. The others are mostly a mistery to me and can't seem to find detailed info on them. I'd appreciate any help. Thanks.
Im looking for the same info.
Saber said:
Collective guide of CPU governors, I/O schedulers and other kernel variables
I present to you a wonderful collection of descriptions, comparisons and graphs of common kernel variables. Before continuing on the wonderful journey of Linux kernel tuning, please note that I am not responsible for any damage to your device or malfunction. You are in complete control over your device so please do not blindly follow without proper research. While you could use this guide to tune other devices other than a smartphone, I would recommend against doing so.
Guides:
Governors - Part 1: Post 1Governors - Part 2: Post 2I/O Schedulers: Post 3CPU Governor Tuning Guide: Post 4I/O Scheduler Tuning Guide: Post 5Hotplug Driver Tuning Guide: Post 6TCP Algorithms: Post 7Other Important Information: Post 8
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:
OnDemand
OnDemandX
Performance
Powersave
Conservative
Userspace
Min Max
Interactive
InteractiveX
Smartass
SmartassV2
Scary
Lagfree
Smoothass
Brazilianwax
SavageZen
Lazy
Lionheart
LionheartX
Intellidemand
Hotplug
Badass
Wheatley
Lulzactive
PegasusQ\PegasusD
HotplugX
Abyssplug
MSM DCVS
Intelliactive
Adaptive
Nightmare
ZZmove
Sleepy
Hyper
SmartassH3
SLP
NeoX
ZZmanX
OndemandPlus
Dynamic Interactive (DynInteractive)
Smartmax
Ktoonservative\KtoonservativeQ
Performance may cry (PMC)
Dance Dance
AbyssPlugv2
IntelliMM
InteractivePro
Slim
Ondemand EPS
Smartmax EPS
Uberdemand
Yankactive
Impulse
Bacon
Optimax
Preservative
Touchdemand
ElementalX
Bioshock
Blu_active
Umbrella_core
ConservativeX
Hyrdxq
DevilQ
Yankasusq
Darkness
Alucard
Hellsactive
Ragingmolasses
Virtuous
Sakuractive
InteractiveX v2
Alessa
GallimaufryX
AggressiveX
Tripndroid
Wrexy
Xperience
Stockdemand
Zeneractive
InteractiveB
Aggressive
IntellidemandV2
Boostactive
Wave
Barry-Allen
Arteractive
Precognition (PrecoGOV)
Mythx_plug
PegasusQPlus
Yankdemand
HyperX
Despair
Electroactive
Electrodemand
Lionfish
Interextrem
Cafactive
Lightning
ThunderX
sched-DVFS
Intel
Frankenstein
Cyan
TheSSJactive
Chill
sprdemand
Kraken
Ironactive
Nebula
Relaxed
Crazyactive
thenewbeginning
Cultivation
Schedutil
pwrutilx
blu_schedutil
Descriptions:
HMP Governors
1: OnDemand:
Description:
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:
Description:
Basically an ondemand with suspend/wake profiles. No further optimization was done to Ondemand to keep it close to source as possible.
3: Performance:
Description:
The performance governor locks the phone's CPU at maximum frequency.
4: Powersave:
Description:
The opposite of the Performance governor, the Powersave governor locks the CPU frequency at the lowest frequency set by the user.
5: Conservative:
Description:
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:
Description:
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
Description:
Min Max is a governor that makes use of only min & maximum frequency based on workload... no intermediate frequencies are used!
8: Interactive:
Description:
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:
Description:
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
Description:
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:
Description:
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
Description:
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 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:
Description:
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:
Description:
The same as the Smartass “governor” But MUCH more aggressive & across the board.
15: Brazilianwax:
Description:
Similar to smartassV2. More aggressive ramping, so more performance, less battery
16: SavagedZen:
Description:
Another smartassV2 based governor. Achieves good balance between performance & battery as compared to brazilianwax.
17: Lazy:
Description:
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:
Description:
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
Description:
LionheartX is based on Lionheart but has a few changes on the tunables and features a suspend profile based on Smartass governor.
20: Intellidemand:
Description:
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:
Description:
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:
Description:
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:
Description:
Building on the classic 'ondemand' governor is implemented Wheatley governor. The governor has two additional parameters. Wheatley works as planned and does not hinder the proper C4 usage for task where the C4 can be used properly. 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.
Wheatley is a more performance orientated governor as it scales more aggressively than ondemand and sticks with higher frequencies.
24:Lulzactive\LulzactiveQ:
Description:
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
Description:
The Pegasus-q / 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
Description:
It's a modified version of Hotplug and optimized for the suspension in off-screen
27: AbyssPlug
Description:
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
Description:
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
Description:
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
Description:
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
Description:
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
Description:
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.
33: Sleepy
Description:
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
Description:
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 developer sets it to. This is a more smoothness oriented governor which means that it is good for performance, without sacrificing much battery life.
35: SmartassH3
Description:
The SmartassH3 governor is designed for battery saving and not pushing the phones performance, since doing that drains battery and that's the one thing people keep asking for more of. Based on SmartassV2.
36: SLP
Description:
It is a mix of pegasusq and ondemand. Therefore, it has a balance between battery savings and performance.
37: NeoX
Description:
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
Description:
ZZmanx is exactly the same as ZZmoove, 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
Description:
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)
Description:
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
Description:
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
Description:
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)
Description:
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
Description:
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
Description:
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
Description:
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
Description:
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
Description:
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
Description:
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
Description:
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.
Click to expand...
Click to collapse
You can find all the info in this thread