yashsingh1/xdaforums huggingface dataset:
[Galaxy S II General] Myshkinbob:
With all due respect to your training, if you're arguing a fully loaded 1.2GHz dual core cpu uses less power than the screen, you're plain wrong. You can test this fact by forcing your screen to stay on and leaving the phone idle on the homescreen. Repeat the same test with a cpu benchmark looping. Your battery will drain at the very least twice as fast, try it.

Also, my example was simplified but there is a known relationship between cpu voltage and power (power which in turn is supplied by the 3.7v battery). Most overclocking sites use P = C * V^2 * f, where C is the capacitance of the chip and f is the frequency. V^2 is of course vcore squared. Just to be clear on this, the capacitance is essentially the cpu utilisation, as it's caused by the number of actively used transistors on the cpu. This is where the current used by the cpu goes, it isn't sent elsewhere by the cpu as you suggest, it is consumed by the cpu switching transistors on and off. It is super clear than voltage (V^2) acts a multiplier on power consumed, if you make workload (C) and frequency (f) constant variables.

If you want to argue those two points then you need to start posting sources to back up any claims. The android OS battery screen isn't a valid source, you can google about that, it basically makes a lot of guesses (based on a file with suggested values) to compile it's numbers.

This is kinda derailing the original thread so if you do want to argue it, lets start a new thread on the topic of whether the sgs2 cpu only causes a negligible amount (your number is 4%) of total battery drain during heavy load. Essentially you are arguing the capacitance of the heavily utilised sgs2 cpu is so low as to be negligible, thus making the power usage negligible at any level of utilisation or voltage adjustment.

The evidence against this are the graphs posted earlier (taken with an ammeter across the battery terminals, no less) as well as any anecdotal proof made by simply disabling the screen time-out and comparing benchmark to homescreen idle battery percent loss.

What i think is relevant to this thread, is the extent to which using neak's undervolting capability can save you battery power, should you believe that the cpu is capable of being the majority battery consumer.
[Galaxy S II General] nrk_2k:
Ok, how about manufacturer specifications.. The performance tab states that total power at 2000MHz for the CPU that is in our phone is 1.9W

http://www.arm.com/products/processors/cortex-a/cortex-a9.php

This is a far cry from the figures at 1200MHz that are stated.

Also I do not use the stock battery use application. I am using a 3rd party one that to my knowledge uses the on board voltage, current and temperature probes. And with all due respect to whatever electronics knowledge you have (by the way I have built my own CPU before, all be it fairly basic, Have you?) you seem to be missing the fact of thermal dynamics.. If our processors are running at 3W power consumption, we could pretty safely asume that almost all of this 3W is being given off as heat (as it is not being converted into sound, or light). So 3W = 3J/s.. Combine this with a small heatsink being enclosed in a plastic case with no air movement.. That's 1800J over a period of 10mins, or about a 7 degrees (celcius) increase in CPU temperature every 10 minutes (assuming only a small thermal transfer between the heatsink and the outer case). With no air movement, over a period of 30mins, that is a 21 degrees increase in CPU temperature (assuming idle CPU temp is about 25 degrees, the same as the battery) that would mean after 30 mins of playing you have a CPU running at 46 degrees. And after an hour 67 degrees (at which point your CPU stability would be well out the window) Yet I can play games that keep my CPU at 1200MHz all the time, and play them for hours on end while pluged into the charger.. But my phone doesn't overheat, or even get close to 45 degrees. If the CPU was really using such a high wattage, there would be no way that my phone wouldn't get really really hot.

Edit:

I should also say here that I do think that undervolting is good, but that battery saving wise it doesn't do much for the average user (it does however help keep the CPU cooler). Most users wanting really good battery life are looking for 2+ days out of their battery. Playing 3D games for long periods is going to eat your battery. So stating that UV saves a lot of battery at high frequencies (with high load) is pretty much irrelevant regardless of whether or not it is true. As for the display, we do know that this uses a LOT of power because of how bright it is. Brightness and power consumption are directly linked. To achieve the high brightness our displays provide, they have to consume a large amount of power. Hence why this is always the first port of call to extend battery life. :D
[Galaxy S II General] Myshkinbob:
thanks for the link. :)

So our cpu doesn't run at 2GHz, it's closer to the 800MHz power efficient model. In reality i suspect it's somewhere inbetween, since the xenyos SoC isn't actually listed, we don't know the precise configuration. Lets say it's 1W at 1200MHz, that seems a reasonable figure, no? :)

So my question now is, if lowering the voltage has a known relationship with power used, are you still arguing that reducing the voltage won't reduce the cpu-related battery drain by an equal or greater percent? Just saw your edit, so to clarify, i mean you're still contending that lower voltage, completely seperate from temperature related leakage benefits, has no appreciable effect on the power usage of that cpu? This is what's genuinely making me scratch my head here. :)

My experience in electrical engineering is limited, i stated earlier i'm no expert. Regarding the 3W dissipation based on the graphs earlier, i assume the 1400MHz/1300mV entry is the one you're discussing. All i can say to that is we don't know the precise breakdown of which components are dissipating it. Lets be harsh and put 2.5W on the cpu alone. So it's dissipating 2.5J/s. Now it might get really damn hot, and eventually overheat (people's sgs2 overheat all the time, search these forums) but who's to say that isn't possible.

For some more information on typical wattage of a dual core A9 @ 800MHz you can check out the anandtech iphone 4s review:

http://www.anandtech.com/show/4971/apple-iphone-4s-review-att-verizon/15

depending upon the task it's as low as 0.7W when idle on the homescreen, and as high as 2.6W whilst loading a game. Does 3.2W system total for a 1400Mhz dual core A9 seem so absurd now?
[Galaxy S II General] nrk_2k:
I am in no way saying that UV wont make a difference to power consumption. It most certainly will. But the difference to the average user (who's device sits around the 200-400MHz range most of the time (or in deep sleep) is going to be very minimal. The link you posted about the iPhone 4 & 4S has some good comparissons between the power consumptions, but it doesn't state exactly how the measurements were taken. even still, we have to remember that the GPU is seperate to the CPU as far as UV goes, and as far as power consumption goes. And the GPU is going to be at least, if not more power hungry than the CPU. A figure of 1W for the CPU at full whack would probably be about right. and I would say about the same for the GPU. But the screen at full brightness on a full white screen, I would put somewhere around the 3-4W range. The screen has 384,000 pixels, each one being a tiny OLED. If we asume at full brightness they consume 0.01W each (10mW is not an unexpected value for the the brightness) that would equal a 3,840mW or 3.8W power consumption. And screen at full black (regardless of "brightness") should be very close to 0W, as black is produced by turning the pixel off. Hence why I say the screen would be first port of call, then the radio (WiFi, 3G, Bluetooth) devices, then CPU. It would also pay to note that we don't know what kind of voltages the iPhones are running, they could be running higher voltages still than the stock SGS2 ones. Regardless of all of this.. Even if the power savings of UV are minimal or not, they are savings none the less (if your cpu allows you to make them) ;)
[Galaxy S II General] Myshkinbob:
Manitax's linked graphs do have measurements for the full white 100% brightness screen at 961mW (display weiss, helligkeit 100%).

I feel like we've really derailed this thread, so I guess we'll agree to disagree on the exact effect of undervolting, and just agree it has some perceptible benefit in specific usage conditions. Also, you made some very good points. :)
[Galaxy S II General] nrk_2k:
Yeah, his "measurement" seems rather off to me.. at that value each pixel would only be consuming 2.5mW at full brightness (This figure seems excessively low for a screen that is still visable in direct sunlight) but yes you are right.. we are sidetracking... :D so we will leave it at this ;)
[Galaxy S II General] Manitax:
Lol.. Very funny what a big and intensive discussion i started with my post. I did not understand all... Anyways it was very interesting to read! Thank you mates.

Gesendet von meinem GT-I9100 mit Tapatalk
[Galaxy S II General] championc:
Is it a Rom or the Kernel which can dictate / set the minimum brightness that a screen can dim down to. If I turn off auto brightness, I think the minimum brightness is still reasonably bright. I'm using V3RTR3MA with NEAK 1.3.2x and like many users of SGS2's, want to have my phone running as long as possible while running normal every day tasks including exchange push email
[Galaxy S II General] kmilof:
hey, one question, im testing neak 1.3.2x. i flashed the kernel in a clean install, everything is allright by the moment, but i felt the phone a lot warmer using it normally. i haven't changed anything in the kernel, neither oc or uv. it raise from 25° to 34° very quickly.

anyone dealing with something equal?

thanks :D
[Galaxy S II General] nrk_2k:
You may want to lower your cpu or gpu voltage settings, if your phone is getting hot while not doing anything then the voltage settings for the lower frequencies is set far too high. Make sure in the CWM recovery menu to use the "remove voltage settings" in the NEAK options menu. This will make sure that any changes to the stock values are removed.
[Galaxy S II General] celerysoft:
A smooth kernel!!!

But there still a question i want to ask, when i turn on the camera, and i do nothing then screen auto lock, when i unlock it i find the camera will not work ,is this bug fixed?
[Galaxy S II General] ny-hardcore:
hmmm...ota updater in 1.4?

https://github.com/simone201/neak-kernel-sgs2/commit/82b96807729af7f39c6ad4e1a1c4945851978251
[Galaxy S II General] glore2002:
Hello and thanks for kernel N.E.A.K 1.3.2 which I 've just flashed with ROM CheckRom RevoHD v4.

When I start CWM it shows up a message telling me it needs CF-Root 5 or newer. Is it there a solution or advice for this?

Thanks in advance!

glore2002.-
[Galaxy S II General] nrk_2k:
Hi,

This kernel doesn't support the CWM application. It will have it own application when version 1.4 is released. :)
[Galaxy S II General] It_ler:
Results for SpeedMod / Phenomenal / void / N.E.A.K. / Siyah / stock kernels

Everything is specific to my phone, my "normal" usage and my home location. Most values are exact results, but some are rounded. I usually have wifi, synch (three email accounts, calendar and news), Google Talk and Skype on.

For all custom kernels, I was running on Frankenstein XILA2 ROM (Modem: XXKL1).

For stock kernels, I was running on the corresponding stock ROM.

Always using the Samsung's standard / stock 1650mAh battery.

For void.echo I enabled the UV - nothing else.

For Siyah, as it has many, many configurable settings, I have changed nothing - just default settings.

For N.E.A.K. 1.3.x (Lulzactive) I tested VR schedule, Lulzactive governor, only enabled sched_mc and the rest unchanged defaults.

For N.E.A.K. 1.3.x (Lionheart) I tested VR schedule, Conservative governor, Lionheart tweaks, sched_mc enabled and the rest unchanged defaults.

Just tested N.E.A.K. v1.3.3x on default settings, only sched_mc enabled on my XWLA4 Frankenstein ROM and added its results.

Here are my current results:

Benchmarks (in Performance governor if available)

Battery stats

So, N.E.A.K. v1.3.3x is "out-of-the-box" very stable and smooth, but not very battery friendly on my phone.

I gave it a second battery cycle and listed the second/better battery results.

Good kernel, fantastic idea with free OTA Update app, stable, smooth and highly configurable.

Only the battery savings on default settings could be improved IMO.

Good work simone201 !

Keep it going ...
[Galaxy S II General] Manoj143:
Highly appreciable and highly recommeded kernel...good work,man...
[Galaxy S II General] AndroidGX:
Mate, your idea and stats are good but I'am a bit lost with all those percentages everywhere :(

I agree with the fact that 1.3.3x is not very battery friendly, I really prefered 1.3.2x which was overall (but not so significantly) better.

BTW, I sugger you to do at least 3 good cycles of charge/discharges by using normally the phone BEFORE doing all your battery tests, even if it can takes few more days to conclude and add your results, worth the try : huge difference between the first cycle and the 3rd one, believe me.

I'am currently with speedmod K21 and I really like the battery life again over NEAK, but this one was the better for every benchs I tested for ;)

NEAK is a sort of kernel for leet (in the same way as Siyah), and speedmod for newbies "just-flash-and-use" with very good battery efficiencies (never been disapointed about this way). :cool:
[Galaxy S II General] Tyian:
If I flash my Galaxy with NEAK it will count on counter?

Meaning that I will need a JIG devise to reset the counter?

I need to have root acess to install this kernel?

Thanks, I'm a noob in Android devise, I only got my galaxy S2 GT-I9100 2 days ago.
[Galaxy S II General] cimmicola:
my phone is I9100 international. the rom is official XXLA4. I've flash kernel 1.3.3x, but it reboot continuously at the battery charge screen(not seeing galaxy s2 logo).

the same problem occured in 1.3.1 and 1.3.2 but not in the 1.3.0 and before..
[Galaxy S II General] MasselMillerM:
Try flashing this .zip in Recovery, before flashing the Neak.

Only an idea;)
[Galaxy S II General] MasselMillerM:
If you flash it with ODIN you don't need Root before Flashing, and then it will also count on counter;)

When you use CWM method, you need logically Root, but then it doesnt count.
[Galaxy S II General] Tyian:
But here is a way to root the device without add in the couter?

So I can root the device, them use CWM method all without adding the counter?
[Galaxy S II General] It_ler:
Thanks for your feedback !

I absolutely agree that three battery cycles will provide more reliable test results.

As you can see, for the last kernels/versions I am very often running two battery cycles (e.g. N.E.A.K. v1.3.3x and Phenomenal 4.0 Extreme).

As I am very curious about new kernels waiting on my "to do" list, I do not want to run a full third battery cycle for each kernel.

P.S.:

I also agree to your kernel categorization ... at least basically.

But I don't think that everybody who wants and likes "just-flash-and-use" with very good battery efficiencies is automatically a "newbie".

P.P.S.:

What exactly do you mean by "leet" ?

Something like pro, nerd, freak, advanced user ... ?!
[Galaxy S II General] Pfeffernuss:
Yup, correct ;)
[Galaxy S II General] AndroidGX:
You're welcome, your stats is a big help for many people :) Sorry, didn't saw this information, so yes : full->empty 2 times is already very good ;) it's perfect!

hehe, no worries, I was just referring the point that NEAK (for exemple) is much more tweakable than speedmod (undervolt, underclock, init.d support for scripts, etc, those kind of stuff is for explicit public and very technical unlike speedmod :)) but as you say, battery efficiency has absolutely nothing to do :cool:

Well, "leet" word is something that stayed into my brain for a while now since I was a old gamer :D, it's reffering to "elite", and with hackers characters it's more known as "1337" where "3" is the "e" and "7" is the "t" ;) you can find more on google for fun if have a moment to kill ;)
[Galaxy S II General] It_ler:
For older ROMs there is a method to root your phone without incrementing the counter:

zergRush exploit.

Have a look here => http://xdaforums.com/showthread.php?t=1319653

But for newer ROMs this exploit is patched and does not work any more.

You can try it ... does not make anything corrupt if it does not work.

Good luck !
[Galaxy S II General] therion21:
Does the kernel support autobrightness profiles ? (jkay deluxe option wich requires kernel support)
[Galaxy S II General] alinawyx:
Had been using this kernel for a month or so, and i simply love it ;) This is my first kernel that I tried messing with different governors and schedulers. And I guess I find battery life kinda more important to me, and having to browse through some threads about governors and schedulers, I like to ask if there's any chance that you may add in SmartAssV2? Sorry to dig up old post, but I really like to try SmartAssV2 on your kernel. It's just a random question, please don't put it in your heart if you don't like it. Anyway, as much as I would like to donate, I don't have any existing credit cards to apply for Paypal, so I guess I will wait for your new NEAK Configurator app Pro version ^_^.. Thanks for the Great kernel ;D
[Galaxy S II General] simone201:
No way for the smartass2, mostly because it is not designed for samsung cpus but only for qualcomm ones...

Anyway, use lulzactive instead that behaves very similar ;)

Inviato dal mio GT-I9100 usando Tapatalk
[Galaxy S II General] alinawyx:
alrighty ;) thx a lot.
[Galaxy S II General] windowsxelvis:
I am new to NEAK Kernel. After I installed the kernel, my screen shows white lines on right side. It happened in previous versions of Siyah Kernel too and it happens again in NEAK. (disappeared in some versions of Siyah)

Sorry for my poor english. Many thanks if you can fix this problem.
[Galaxy S II General] pants_marshall:
I've only had my S2 since Jan, and NEAK was the 2nd kernel I flashed after rooting. And i'm perfectly happy with it thank you Simone, I get prity good battery life out of my phone so that makes this kernel near perfect for me.:D
[Galaxy S II General] It_ler:
Results for SpeedMod / Phenomenal / N.E.A.K. / Siyah / RedPill / stock kernels

Everything is specific to my phone, my "normal" usage and my home location. Most values are exact results, but some are rounded. I usually have wifi, synch (three email accounts, calendar and news), Google Talk and Skype on.

For all custom kernels, I was running on Frankenstein XWLA4 ROM (Modem: XXKL1).

For stock kernels, I was running on the corresponding stock ROM.

Always using the Samsung's standard / stock 1650mAh battery.

For Siyah, as it has many, many configurable settings, I have changed nothing - just default settings.

For N.E.A.K. I tested VR schedule, Lulzactive governor, only enabled sched_mc (and AFTR idle mode) and the rest unchanged defaults.

For RedPill kernel, I tested completely default settings (deadline / ondemand) without any change.

For RedPill (sio/conservative) kernel, I tested completely default settings, only changed io sched to sio and governor to conservative.

I have just flashed N.E.A.K. v1.4, was running some benchmarks and added its results.

Here are my current results:

Benchmarks (in Performance governor if available)

Battery stats

N.E.A.K. v1.4 is stable and very smooth on my phone.

Now I am running battery tests and will report my results as soon as all tests are finished.
[Galaxy S II General] netban:
Hey all, been using this kernel for a while now but I was wondering, since I'm not keen on the banners (although they look great, not my cup of tea lol), may I make my own?

I don't mind posting them up for others to use too :-)

Thanks, Rizur.
[Galaxy S II General] :
sure man go for it....the more the merrier and i am pretty sure Simone would be happy to have it on his thread:)
[Galaxy S II General] It_ler:
Results for SpeedMod / Phenomenal / N.E.A.K. / Siyah / RedPill / stock kernels

Everything is specific to my phone, my "normal" usage and my home location. Most values are exact results, but some are rounded. I usually have wifi, synch (three email accounts, calendar and news), Google Talk and Skype on.

For all custom kernels, I was running on Frankenstein XWLA4 ROM (Modem: XXKL1).

For stock kernels, I was running on the corresponding stock ROM.

Always using the Samsung's standard / stock 1650mAh battery.

For Siyah, as it has many, many configurable settings, I have changed nothing - just default settings.

For N.E.A.K. I tested VR schedule, Lulzactive governor, only enabled sched_mc (and AFTR idle mode) and the rest unchanged defaults.

For RedPill kernel, I tested completely default settings (deadline / ondemand) without any change.

For RedPill (sio/conservative) kernel, I tested completely default settings, only changed io sched to sio and governor to conservative.

Just tested N.E.A.K. v1.4 and added its results.

Here are my current results:

Benchmarks (in Performance governor if available)

Battery stats

N.E.A.K. v1.4 is the best NEAK version I have tested so far.

simone201, you are doing something the right way !

This kernel is stable, very smooth and has very good battery savings in over-night usage on my phone.

Only in my "normal" mixed usage, there are some other kernels working slightly better.

Overall, N.E.A.K. v1.4 is an excellent, light, stable, smooth and highly configurable kernel with some extras (such as configurator and OTA downloader app).
[Galaxy S II General] Sad56:
Backup Issue

Hello all and first sorry for my bad English.

I post here,because i'm not able to post on the original Thread.

I've resolve the backup issue for me.:)

Like it was said in the Siyah Thread,I've flash the kernel clean script v2.4 and the gs2Blitzer v1.5 too.

And now all is fine,I've make 3 backups and restore all works fine.

I hope it help.

And @Simone your kernel rock :D (the best for me)
[Galaxy S II General] edwardeutsch:
Hey guys i'm a nooob! but i can say that this kernel with magic config is the best ever made! for me obviusly! ;)
[Galaxy S II General] lestat1929:
Hi,

I think NEAK is a great kernel, but looking on It_ler´s result, the latest speedmod is the kernel in terms of performance and battery use out of the box...

Do I have a wrong opinion?
[Galaxy S II General] It_ler:
Just to clarify:

1. My test results are only saying something for my phone and my "normal" usage.

2. Some kernels (like N.E.A.K.) are highly configurable (io sched, governor, UV, UC/OC, etc.) and I tried to test always using the default settings (=> out-of-the-box). So these kernels will have better results after customizing to the phone they are running on.

3. I do not want to judge between kernels in general. I just try to test them under nearly same conditions and share my results.

So, be inspired to flash some of the tested and very good kernels to your phone and test them yourself ... on your phone and with your "normal" usage.

Then you can judge a kernel for your phone.

4. My tests are one one view. We all can get a better overview with more and different tests/results. So, everyone who has a little bit time and is willing to do and share his/her tests, please do so.

That could give the kernel developers more reliable feedback to enhance their kernels ... maybe.
[Galaxy S II General] lestat1929:
Hi It_ler,

you´re right. I have great battery life with speedmod and phenomenal. Now i´m testing NEAK with exterme undervolting, and a bit customization... everyone have to decide about the best personal kernel/settings, but your tests are always a good guideline.

Thank´s a lot for the time you take to test for the community.

"Das passt scho" :D

Regards

Antonio