Develop Bugs

[Q] Power Consumption and Clock Speed...

Question: if the kernel will go into deep sleep whenever it has nothing to do, what is the benefit in regards to power consumption of pinning the clock speed real low when the screen is off?
I ask because common knowledge, at least from what I've seen around, is that the low-clock "screen off" profile is common sense. But today I tried not having that profile, and I see that the CPU goes into deep sleep a lot more time now, and my battery life is the same if not actually better than before.
True, ROMs and kernels are still changing so much that it's difficult to dedicate enough time to one configuration to actually determine it's efficiency over time, which is why I wanted to throw this out here, see if anyone with more knowledge can answer.
If the CPU is under a certain amount of load, I would imagine that, for instance, in an Ondemand governor with a very low Up Threshold, the CPU will spike to a high speed until it's done, then sleep the rest of the time until the next load. If constrained to a low clock speed, it'll work on it, slow but steady, until it's done.
Is the high voltage required for that spike offset by the voltage savings of going to sleep, and is the total voltage consumption at the end of the load lower than the alternative, that is, stick to a low clock cycle, consuming what I assume is lower voltage, but for a longer amount of time? Is voltage consumption as clock cycle speed increases linear, or exponential?
If the power consumption increases exponentially as clock speed increases linearly, then it might be better for power consumption to restrict the processor to lower speeds. But if power increase is linear, then it would be better, I believe, to let the CPU finish with it's load as fast as it can, so it can go to sleep faster.
Any thoughts, ideas?

To Quote from Wikipedia's Overclocking page:
Increasing the operation frequency of a component will usually increase its thermal output in a linear fashion, while an increase in voltage usually causes heat to
increase quadratically
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I know nothing about the Galaxy S II specifically, but most Android phones scale both voltage and clock-speed together, leading to exponential power increases when clocking up. Thus, in theory, you should see better battery life with a lower CPU limit with screen-off.
If in your case you have constant voltages across the board, that would explain why you see no benefit from a screen-off profile.
Finally, if you do have constant voltages across clock-speeds, then you probably could lower your voltages at lower speeds and thus realize a benefit.
YMMV, of course

Yes but if you have processes running in the background like large file downloading then the phone won't be able to process any of them
Sent from my SGH-T989 using xda premium

Setcpu Profiles

Hey guys, I'm just wondering what settings do you have on your setcpu for the best performance and battery life? I'm totally new to this lol
Sanks

kazemagic said:
Hey guys, I'm just wondering what settings do you have on your setcpu for the best performance and battery life? I'm totally new to this lol
Sanks
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i i think that ondemand is the best for daily using... i'm using cm10 rom and i have some music problem so i'm using interactive and it's ok. if you don't use games or heavy apps, you can underclock it to 1ghz or even less and put on powersave.. but you have to try and find the best for you

My setup is a little complicated. I use the ondemand governor, then for the profiles I make it use powersave and under 760mhz between 1am and 8:30am which seems to really help during the night. Also set it to use 760mhz max when the screen is off.
When charging or above 40% battery I allow it to run full speed, but only when the screen is on, therefore helping charge times. On charge or above 80% I set the governor to performance.
In call I set the clock to max 1000mhz and conservative to try and allow calls on low-battery to work properly without lag but also without killing the battery.
I have a couple of other options set for very low battery ( < 12% ) too, but those are only to extend the battery if it's dying.
I wouldn't say all this is necessary... but I need my phone to keep working at all times as I use it for receiving business calls.
It's just a matter of playing around really... depends what you use the phone for. For the most part tell it to use lower clock speeds when you don't need them so much (when phone is off, during the night, during call etc) but you will really notice the speed difference if it's underclocked while you use it, so I tend to allow it to use full whack when screen is on, unless the battery is low.
I also set up profiles to make things like Bloons TD4 run in performance mode and min of 1000mhz, to keep them smooth . Drains the battery though!

lol setcpu does a really good job at battery saving. When using ondemand, my phone can last more than 2 days (if it's on standby)
Have you guys tried under-vaulting? What does it rlly do?

kazemagic said:
lol setcpu does a really good job at battery saving. When using ondemand, my phone can last more than 2 days (if it's on standby)
Have you guys tried under-vaulting? What does it rlly do?
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If you mean decreasing the voltage on the CPU, no I haven't. From my experience in desktop PCs however, if the CPU voltage is too low it can lead to hardware issues and instability.
If something needs a certain amount of power, and you give it less, it will either try and draw more amps which increases heat and can fry components, or won't work properly. You could probably "under-volt" the CPU at the same time as reducing the clock speed however, but your performance will suffer. When the processor is set to be ondemand it underclocks itself when not in use anyway
The biggest battery drain is screen and radios, concentrate on using them less. Underclocking the CPU will make the phone last longer when in use, but usability will suffer and turn your super fast smart phone into a sluggish one. I only make mine stay underclocked when the screen is off, during a call, or on low battery. During general use I let it do its thing .

UV(Under volt) is actually not to bad. Don't ever set those values at boot, else when they are too low, it will cause BOOTLOOPS. It just reduces the amount of power allowed for the cpu to use, thus it won't use more than required. You can't really ask a person for his/her uv values, as no 2 chips are created equal.
People stating that they UC(underclock) their device is not quite right. We don't have much control over our cpu's to be honest. If you run tegra stats whilst using you're phone, you'll see what I mean. It will sometimes(happens quite often) just bump up to higher frequencies to which you UC them. Also as soon as the screen is locked and unlocked the max cpu frequency set by the governor will just return(for example: say stock is 1500mhz, and you set it to 1400mhz, it will return to 1500mhz after an unlock). Ondemand is very very good for battery and performance. But remember you have to tweak those values individually in order to optain the best possible performace for the given task you want. Whether it is for battery or performance.
It's actually also a lot better to just tweak those values as to TRY and uc. Uv will stick, UC not!
Here is a small example as to battery saving and performance values for ondemand governor:
sampling rate:---------60 000 ----- 30 000
up threshold:--------------95 ----- 60
sampling down factor:-------2 ----- 8
powersave bios: ------------3 ----- 0
ignore nice load:------------0 ----- 0
io is busy:------------------0 ----- 0

[Q] Has anyone ever underclocked One X?

So I tried to underclock my One X to around 640 MHz and it was running VERY smoothly and stable with only 2 cores active. I was using the ViperX 2.2.1 ROM and the Kernel was the no OC NCX 0.99a. The battery life wasn't bad, but has anyone tried underclocking to 1 GHz or lower? If so, how is the battery life and what kernel and ROM did you use?

With SetCPU you can change the max. CPU, but why should you? When the phone doesn't need much processor power, it just scales down by itself.
So, it already has the best underclocker there is.
Mayby you could try undervolting to save even more battery, but that means the CPU can be somewhat less steady.

im trying to get my head around UVing / UCing my HOX. is there any guide around? im trying to search through the forum but still no luck.

ricopoetra said:
im trying to get my head around UVing / UCing my HOX. is there any guide around? im trying to search through the forum but still no luck.
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underclocking means the CPU runs slower so should use less battery but slower CPU speeds also means to takes longer to preform tasks which could use more battery, check on google most places say its not worth it as that battery saved is tiny and not worth the drop in CPU performance.
undervolting however lowers the voltage that CPU uses while working this does save power and also lowers heat (less voltage less heat) but if you lower it to much then the CPU becomes unstable due to lack of power and well crashes and restarts the phone in most cases.
to get the best out of undervolting you need to lock the max CPU speed to each step (CPU speed, 300mhz, 600mhz and so on) and slower the voltage and then run a bench mark (like antutu) and see if its stable, if it is you lower the voltage again and repeat until it crashes at which point you have found the lowest voltage that the clock speed can handle so you jump up a voltage then more on to the next speed.
it takes along time but that would get you the best undervolt your phone and hardware could handle.
or you can just use the global to lower the voltage for every speed, this is much faster and much less time consuming but you don't get the most out of it.
for this you basically drop the voltage then use your phone for different things; browsing, games, benchmark and see if it crashes if not lower again till it does then go back up a step.

thanks for explaining. I'm getting some of the points that I missed Awhile ago. I guess I'm going to try the longer way of doing it.
Sent from my White HOX JB PA 2.10

Underclocking and Battery life?

hi,
I am running stock jellybean with franco kernel. just wondering what is the optimal CPU setup that doesnt sacrifice too much performance while increasing battery life. Im not too concerned about games as I rarely play them. I ussualy use the phone for music, calls, text, email, and webbrowsing.
I am using the Franco updater app. I have 1228 max, 230 min
and screen off max is 384.
I also noticed in cpu spy that my highest two frequencies 1036, 1228 are combined less than 10%.
with all that information, what do you suggest?

hshaikh said:
hi,
I am running stock jellybean with franco kernel. just wondering what is the optimal CPU setup that doesnt sacrifice too much performance while increasing battery life. Im not too concerned about games as I rarely play them. I ussualy use the phone for music, calls, text, email, and webbrowsing.
I am using the Franco updater app. I have 1228 max, 230 min
and screen off max is 384.
I also noticed in cpu spy that my highest two frequencies 1036, 1228 are combined less than 10%.
with all that information, what do you suggest?
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Click to collapse
I suggest to decrease your max CPU until you feel it affects performance too much. You can also try switching to a governor less aggressive than interactive (try ondemand).
Don't expect magic though. I've played with decreasing max CPU clock, max CPU screen off, governor settings etc with three different kernels. Gathered stats for at least one week each time. Never noticed a difference large enough to actually matter to me. For maximizing battery life, you can gain more by hunting apps that cause a lot of (partial) wakelocks and alarms, and use low screen brightness.

hshaikh said:
and screen off max is 384.
with all that information, what do you suggest?
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Click to collapse
don't limit screen off cpu speed to 384. it will take longer to perform operations under wakelock, thus killing of more battery than it actually saves.
it would be nice if listening to music, since it's not an intensive task and it requires constant cpu usage. still, you'll most likely have stuff syncing in the background so i don't think you're doing any good by limiting it to 384 on screen off.

power isnt going to be conserved with lower clock speed. lower clock speed means it takes longer to finish the task. to conserve power, your phone has to do less. for example, lower brightness, no sound, less/no syncing.

Darunion said:
power isnt going to be conserved with lower clock speed. lower clock speed means it takes longer to finish the task. to conserve power, your phone has to do less. for example, lower brightness, no sound, less/no syncing.
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Well, there is an optimum somewhere. Higher CPU speed means tasks are executed more quickly, but higher clock speeds also draw more current from the battery. I agree that tweaking this has little effect on battery life though.

Petrovski80 said:
Well, there is an optimum somewhere. Higher CPU speed means tasks are executed more quickly, but higher clock speeds also draw more current from the battery. I agree that tweaking this has little effect on battery life though.
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you are correct. there is a magic middle ground because power consumption doesnt scale in a linear way. but finding that spot would take massive testing and even getting to the center, would still probably only gain about 10-15mins average use on a battery charge :/

bk201doesntexist said:
don't limit screen off cpu speed to 384. it will take longer to perform operations under wakelock, thus killing of more battery than it actually saves.
it would be nice if listening to music, since it's not an intensive task and it requires constant cpu usage. still, you'll most likely have stuff syncing in the background so i don't think you're doing any good by limiting it to 384 on screen off.
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what speed show i set to max when screen is off.

did you read anything that Darunion and Petrovski80 wrote? I keep mine at it's max, i don't care, i don't live in the woods with no electricity.

thanks for your inputs. i have experimented and I found out that changing the cpu speeds has minimal effect of battery life. the clock speed is not killing the battery the screen is. no matter what cpu settings i use i get 3-4 hours screen on time.
if i dont use the phone alot that day (like 1 hour screen on time) the battery will still be 40% after a day.

hshaikh said:
thanks for your inputs. i have experimented and I found out that changing the cpu speeds has minimal effect of battery life. the clock speed is not killing the battery the screen is. no matter what cpu settings i use i get 3-4 hours screen on time.
if i dont use the phone alot that day (like 1 hour screen on time) the battery will still be 40% after a day.
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Exactly. I get similar performance.
Sent from my Galaxy Nexus using Tapatalk 2

[Q] battery is very hot

Hi,
When I use from my phone and run game (not high end) ,back of my phone getting very hot and burning my hand.
life time battery without play gaming and just send several sms and little talking is one day also i installed power saver app.
What can i do about it? battery is corrupted? or is other problem?
please help, i buying this phone 20 days before.
thank you

I was having the same issues when I first got my G Pro... I called LG tech support and they Had me do a soft reset....
Pull out the battery with the phone on.
Leave the battery out for 5 minutes.
Replace the battery, and turn in G Pro..
Solved my hot battery problem....:thumbup:

The main culprit is the ondemand governor that kicks up the CPU frequencies to max (1.7GHz) with just the slightest touch. Doesn't matter what kind of games you play, it's still stressing the CPU. Since we don't have any stable / feature rich kernels providing the better governors, interactive is the best bet to reduce heat and save battery life while not making a noticeable hit on performance. Only noticed a 2 fps drop when doing the benchmark on Epic Citadel with it on the highest quality. Still nice and smooth!
Sent from my Vanir 4.3 LG-E980

my battery usually 41.2degrees

李春雷 said:
my battery usually 41.2degrees
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should be only mid 30s. My current temp is 23C. I run interactive.