yashsingh1/xdaforums huggingface dataset:
[Galaxy S II General] m444266:
...hmm.. God gave us brains to understand certain things that we cannot see with our eyes like electricity, etc and how they work... but if even these things(science as we call it) eludes us then...:rolleyes:

like I said, will test this too.
[Galaxy S II General] anvoes:
Battery life test with T39

First of all: thanks to hardcore for his work on the kernel!!

I just finished a battery life test with the SpeedMod T39 kernel and here are the results.

I tried to have the same test environment as m444266 in his initial posting:

WiFi always on

Phone (UMTS) always on

Screen (max. brightness) always on

Plain white wallpaper as background (no widgets on screen)

Basically no usage of the mobile, just checking the battery info page from time to time

No UV/OC modifications

Lite'ning ROM v6.1

I kept the device on and running until it shutdown itself because of no more juice. I was lucky to be able to get the final screenshots though.

In this test scenario i got 5h 47m running time. BTW, deep sleep is basically working on my device with T39.

While doing the test i was thinking about if it wouldn't be better to switch the device to flight mode as the WiFi and phone reception conditions might vary quite a lot and are draining the battery faster.
[Galaxy S II General] ithehappy:
Enough talking, now time for me to post second screen shot of my usage and the last. Only one word coming to my mind, LOL.

Going back to CF kernel with Non UV settings without SetCPU, PERMANENTLY.

Best of luck to this thread.

Period.
[Galaxy S II General] stefanjadex:
Very nice, what ROM are you using?

Regards,

Stefan
[Galaxy S II General] Rinoko72:
Almost Stock Rom

I'm running stock KH3 rom with CF root & 1 little battery mod (to get %), used Titanium to lock down a few of the standard "samsung" apps which I never use.. ;)

So after a "normal" day at work (syncing 1 email acount every 15min, a bit of Wifi before going to work, a few phone calls, a few sms) and half the time having really bad cell signal I've still got 90% battery :) after I'm home..

I think that this is very acceptable for such a powerhorse of a phone, with my old HTC desire I'd would maybe only have about 70% with about the same usage..

Is there really that much power to be gained by going over to a custom ROM or playing around with the CPU setting??

If I play around with my phone all afternoon/evening, I can always manage to empty the battery, but then I used my phone more that my pc :p, but by just using my phone as a "phone", I don't think getting though 2 whole days and maybe start a third is a problem..

Cheers.. :)
[Galaxy S II General] pspilot:
Listen mate, I don't need a picture of the earth to know it's round - same goes for laws of pysics ... you know, the stuff that keeps us all on the ground and makes water flow downhill, no matter where ... also a law of physics :D. I don't care if you negate the effect of "lesser voltage = lesser power", it remains true nevertheless and the whole semiconductor business is working with some solid formulas about it. Your signature is just ridiculous. If you can't see the effect of undervolting, you're just doing something wrong with your tests - it's that easy :).

However, how much UV is saving for someone is a different story and depending on the usage. But the point is, no matter how little the effect is, it costs nothing. Samsung just sets a voltage that is safe for every phone, everywhere at any temperature etc. etc. If your CPU is working with 10% less, you're saving power without any cons.
[Galaxy S II General] Fruktsallad:
Word. QFT. And so on. :)
[Galaxy S II General] s2d4:
As someone mentioned previously, you need to test at every step.

The classic stability test only tests the stability of the highest clock rate.

The scaling stability seems to test more of the step transition then at the particular step. The time spent in each step will be rather short if you have even more steps than stock.

So pretty much to do it properly, we should probably do both of the above tests.

Benchmarks with different conditions doesn't make much sense either.

Anyway, I see you've made a decisions based on what you understand. Because of that, I would definitely recommend stock rom and stock kernel for your level of usage.
[Galaxy S II General] m2smoe:
I don't understand what you're supposed to be proving with these screenshots? I've posted screenshots with 7h screen on time and over 2 days total uptime without charge, you've seen them. What the heck are you going on about?
[Galaxy S II General] anvoes:
Back to the topic: there is no doubt that lower voltage means less consumption. The question is: how much less? Will we notice it in real life usage? Will we at least see any significant difference in a whatsoever test scenario?

I tried to figure out what test scenario could be adequate for making assumptions what UV might give for real world usage. But no idea yet.

The way i did my test was just the way user 44266 was doing his tests. Basically this means that the device is running all the time with 200 MHz. An app which is doing some kind of busy work and which is able to control the frequency the device is running with would be a solution. Something like stability test, but for battery test purposes.

Until now I haven't found any real proof that UV has a significant effect. Pointers are welcome.
[Galaxy S II General] Bonestack:
Maybe setcpu uses more juice than undervolting alone saves? Just a thought, I'm running undervolt + underclock (Oh and sorry I mentioned earlier I could do tests but I'm too busy atm)
[Galaxy S II General] Fruktsallad:
I searched this thread and didn't find this link already in place, so I'll pop it in here.

Basically, during their testing, it clearly shows the advantages of undervolting. We're not talking huge numbers here, but bear in mind that these are tests with the screen on all the time. With more "idling" there are likely more minutes to be gained.

The article is in swedish, but the diagrams are in english. Just pop the link in google translate if you want to read the whole article.

http://www.nordichardware.se/test-l...kt-pa-laengre-batteritid.html?start=3#content

Cheers!
[Galaxy S II General] Nebucatnetzer:
Don't think so. I reckon SetCPU is more like an interface to change values in different files. It write them ones and after this there is no more need for it to run. Because the kernel takes the infos directly from the files.

But I could be wrong.
[Galaxy S II General] kmax.pt:
great topic! helpfull!! thanks
[Galaxy S II General] __NBH__:
Under volting does save some battery life but with set cpu you can only change the voltages at the different cpu speeds. I assume when the phone is in deep sleep it is using a cpu speed not on the list so standby battery drain seems to be pretty similar across the different kernels I've tried.

My best was back on kf3 with villain rom and no under volting and I got 5hrs 7 mins screen on time with 24% battery left, recently with villain rom and ninphetamine 2.1.3 I got 5 hrs 43 mins screen on time but with 2% battery left.
[Galaxy S II General] pspilot:
Actually there's no speed at all, when the phone or rather the CPU is deep sleeping. It's also called 'halt state' and the CPU needs external events to wake up again. That's also the reason, why there's always a tiny wake-up lag since it takes a bit longer to start up the CPU clock again. External events are mainly interrupts caused by buttons, sensors or the real-time clock to name a few.

SetCPU doesn't consume power for undervolting once the voltages are set and SetCPU is terminated again.
[Galaxy S II General] s2d4:
btw, this test benefits the kernels with lighting levels modified, if a kernel developer has incorporated this, he can pretty much modfy his kernel to suit this particular benchmark method...

example:

Speedmod

K1-T39:

- Modified brightness levels, higher mid-level brightness

- Slight optimization to light sensor driver
[Galaxy S II General] m444266:
RaveMod v2 T27 on LR6.1 out.

Done testing rageMod v2 T27 on LR 6.1. took me a while to finish this due to bad timing.

ANYWHOO... next up.. same kernel but UV'ed
[Galaxy S II General] chonshon:
Would you also try RageMod v1 T26?

Because I got better battery life with v1 T26 than T27, I want to confirm it.

Thank you a lot.
[Galaxy S II General] m2smoe:
ithehappy: here you go :)

almost 24h uptime, almost 7h screen on, with HEAVY use, browsing web, playing games (1h30 total).

You all done? :)

Oh, and for the record, this is with CM7, no UV/OC. If I was on Revolution ROM, with setCPU running, I would get even better stats. And that's the stock battery, btw.
[Galaxy S II General] rocketpaul:
angry birds is a great game, clearly very addictive lol:)

God knows how you get these stats all the time, are you using cm7's latest build?
[Galaxy S II General] m2smoe:
Yep, nightly 39. You just need to configure the phone properly, watch which widgets you use, what drains battery, what causes wakelocks. If you're careful enough about that, the battery will last long with no problem. And ye, angry birds is so addictive :D
[Galaxy S II General] ithehappy:
I hate coming in this thread but had to come to reply to your ......

You really think you are clever right?

Now I am gonna post the same Display On time with CF kernel, with an hour of Angry Birds, then I'll tell everyone how you are posting those crazy results!

Just wait till tomorrow ;)
[Galaxy S II General] stefanjadex:
I read this thread every day, looking to find the best way to improve the battery life of my SGS2.

I've tried many roms and kernels, but I have never succeed to reach more than 2 h 30 min screen time till battery empty.

As I see, there are peoples who reach more than 5 hours of screen time from a full battery.

As I read and as I discovered, the screen is the most power consuming.

Does anybody know if there are different types of displays for SGS2? Maybe, if this is true, one type of display is much more hungry than the others.

Mention: I'm almost sure that I read something about this somewhere...

Regards,

Stefan
[Galaxy S II General] anvoes:
@Stefan

Some posts ago i posted my battery test using a well defined test procedure. In this test case I got about 5h 47m. If you get just about 50% of that using a similar test environment, something is obviously wrong, IMHO.

Possible reasons for this:

1) Bad phone signal reception is eating memory. Same applies to bad WiFi signal levels. Try to make a test in flight mode in order to see if there is an significant change.

2) When you do a similar test like me, CPU spy should show that the device is running with 200 MHz most of the time. If not, some processes are running and eating memory.

Finally, it would help if you describe more detailed what test you are doing and possibly post some screenshots showing the results (see my screenshots as an example).
[Galaxy S II General] kwerdenker:
Samsung will probably release an SGS2 version with a SuperLCD display instead the Super AMOLED+ like they did with the original SGS. That version should then have a different type number like GT-I9103 or something but at the moment all SGS2 have the same display type.
[Galaxy S II General] lufc:
Once again a Thread full of crap meaningless Arguing Stop it i am sick of cleaning up this crap there is no need for it.

Please keep this thread clean and on TOPIC with no arguing we all have views right or wrong just accept it

Any one goes of topic will get a holiday and this thread will be Closed

You have been WARNED
[Galaxy S II General] m2smoe:
This is a topic about battery life and we're arguing about... battery life? Or am I missing something?
[Galaxy S II General] m444266:
guys, you heard the man.. please, if you can, contain yourselves from arguing and posting (as the man put it) "crap".. you can type what you want to say, reread them and if it has that aggressive tone or somewhat an attack/counterattack direct to someone, do your best not to click on submit.. or tone it down make it a bit more constructive if possible/necessary. Indeed it is about battery we are arguing about but..the man has control and could send this thread to oblivion.. so... no argue, just discussions.

There are things beyond our control. If we can't change them, best to change our attitude towards them.;)

If I have the time, sure.

-----------

ANYWHOO.. Note: indeed my tests run mostly (not all) on 200Mhz even with the current testing on UV simply because I just leave it there with a white BG and don't do much and clockspeed adjusts itself accordingly if "ondemand" I believe.. This may not reflect real world usage but again, its not about reflecting real world usage. just take it in to proportion for other clockspeed. Assumption is if UV'ed, I will get longer life even if I'm mostly on 200Mhz.

ps.1. if you could resize your screenshots, please do.. its humongous ;)

ps.2. thanks to all (just in case) who participated in this thread. those who found the information useful, those who thanked me(your welcome btw), those who even just viewed, thank you for coming here. :D
[Galaxy S II General] Razer(x):
Sorry but i can't understand how could you compare kernels doing different things. Even a minute of gaming can be rilevant
[Galaxy S II General] Hacre:
All of these posts are spot on and it's amazing how many people are literally arguing that they're proving the laws of physics wrong.

It's still active for controlling the CPU clock if you use profiles, but if it was a battery drain you'd see it in the battery stats.
[Galaxy S II General] brack11:
I'm using jeffrey speedfrey kernel and it gives excellent battery lifer but his thread its closed because of GPL violation. What would be other kernel which maybe even better than this one.

I don't know how right are my calculations, but it looks like setcpu itself eats more battery than saves.

Sent from my GT-I9100
[Galaxy S II General] Piercy0812:
This is how i improved my battery life. Includes, undervolting, external batteries and all of those snazzy things you guys like:
[Galaxy S II General] n-gineer:
Hi there battery life enthusiasts. Here are my observations made on stock kh3 plus cf-root kernel - see attachments.

In brief: 23 minutes of phone calls, 51 min movie at 100% brightness, edge most of the day on, the other part of the day wi-fi, lots of opera browsing. Screen was mostly at 40% brightness.
[Galaxy S II General] chrisjcks:
I gave up trying to UV, when i lowered it by 25, i could run stabilty test for over 10mins without errors, yet as soon as i opened an app - the phone froze.

Something not right...
[Galaxy S II General] Hacre:
If it runs fine at stock settings, then everything is fine. UV/OC/OV is the process of running the CPU outside of shipped specs. It's not outside the realms of possibility that you ended up with a SoC that just scraped through the stability testing.
[Galaxy S II General] chrisjcks:
To be honest hacre, i dont think i understand the process properly.

I was setting setcpu to 1400mhz max and 1400mhz min so it runs at just that speed, then lowering voltage 1 notch (-25) and running a stabilty test for 10 mins.

No errors, yet i opened up vampires live app, and the phone froze before it even loaded up.

Not sure those stabilty tests do anything, as opening an app should be less stressful than a stress test app.

Its all confusing.

Ive also tested other speeds and managed to pass stabilty tests at UV settings, only for them to fail on boot or on wakeup from lock screen.
[Galaxy S II General] m444266:
RageMod v2T27(again..but) UV'ed results out

why not just change scaling from "on demand" to "performance" instead of setting min frequency to 1.4Ghz.. if scaling set to performance it will always run at max speed, contrast to powersave which will always run on min frequency.

if it fails on wakeup from lockscreen and probably on scaling "ondemand", perhaps the lower frequency settings are at fault..??

ANYWHOOO... results for RageMod v2T27(again..but) UV'ed results out
[Galaxy S II General] s2d4:
Don't do it if you don't understand, and don't advice others on it either. 10 minutes is not good enough, scaling test won't even have much of a chance to test transitions between all the steps, and the classic test only tests the highest step.

Read my reply to u from the other thread, u even called me wrong on this same issue u failed to comprehend.
[Galaxy S II General] s2d4:
@m444266

I posted earlier about developers making lighting adjustments, r these benchmarks still valid then?
[Galaxy S II General] m444266:
yes because I test using the highest possible brightness all through out.
[Galaxy S II General] s2d4:
What if that highest brightness is now altered to be different?? ie lower. Thus a reduction from any others with standard levels. This is what i was referring to, not the lighting level transitions.

To suit this benchmark, for best benefits, is to reduce brightness at the lights driver level. Almost like the cheat script for quadrant benchmarks
[Galaxy S II General] rab1412000:
ragemod v2 t27 u/v is 'only' as good as v1 with no undervolt.

does anyone know what update 2 specifically does? are these the supposed security patches?
[Galaxy S II General] m444266:
thus, battery life is longer if indeed brightness level is lower.

anywhoo.. i wish UV-possible kernels would incorporate governors such as smart*ss and those others.. that would be interesting to test with periodic change of scale like 200Mhz>1200Mhz>DeepSleep cycle 20minutes each..
[Galaxy S II General] chrisjcks:
You were wrong....

You say JD doesnt affect voltages, regardless if it does or doesnt (thats not the issue)... Its stable at 1400mhz. (if its using stock 1300 voltage, then its even better than setcpu as that needs 1350 to be stable)

But you couldnt see this...

So because i ask about stabilty testing regarding setcpu in this thread, dont try and use it to correct your bull**** from the past in another thread. :)

Ive ran the setcpu test for an hour, and it ran without errors - did the phone freeze on boot, YES.

My post was to question the so-called stabilty tests, yet you couldnt resist trying to push your gospel - like i told you before, you do it your way, ill do it mine.

To think your better than others and that people asking questions dont know how to overclock or undervolt is just pure ignorant on your part.

So please, ssshhh.
[Galaxy S II General] chrisjcks:
Im currently testing:

Villain rom and ninphetamine 2.1.3

1400mhz/1325mv

1200mhz/1200mv

1000mhz/1100mv

800mhz/1000mv

500mhz/875mv

200mhz/850mv

On-demand with screen off profile 200-500 (also on-demand)

Not sure if these are any good for what this phone can 'possibly' do, but will try to push my phone further if possible.

however, what i know for sure is - those stabilty tests mean nothing. (ive had mv voltages run stable on stabilty tests for 200mhz under 600mv... But trust me, it aint stable.)

I believe alot of people are running these tests and believing its stable if it returns with no errors, my point from the post above is that these are not to be trusted. :)

... At least not from my experience with them.
[Galaxy S II General] pspilot:
It's like you'd say "What people say mean nothing". Some (most? :D) are telling bull, but not all. Stability tests are usefull ... in general. The problem is, OC/UV a young 'discipline' in mobile computing, so the stability apps out there might not be perfect yet - to express it friendly. If a programmer knows the CPU and the architecture of the machine, he's very well able to write a stability test that works.

Second thought, all these posted voltages mean little to anyone else with a different hardware. Same goes for the evironmental conditions. You can run the best tests for days and find the perfect voltages - you still might get a wonderful crash when the temperature changes by 10 or more degrees. That's exactly why Samsung uses the voltages they use.
[Galaxy S II General] s2d4:
600mv at 200mhz?? Kernel caps it at 800mv.....

Meh. Not worth bothering to explain it, let him do what he wants coz he is right..
[Galaxy S II General] chrisjcks:
Really?

Setcpu shows i can use 600mv.
[Galaxy S II General] chrisjcks:
Yes, i understand all this, i agree with it all.

I should have said 'the current crop of stabilty tests available are nonsense'

I posted the voltages im at at the moment incase someone said 'you may be able to squeeze more out of your 1000mhz voltage...' etc.

The phones cpu is a little unknown to its boundries and only posting and chatting with fellow overclockers/under-volters will push these boundries.

s2d4 If you have no help to offer or something worthwile posting thats on topic - then dont post.
[Galaxy S II General] freaked:
Thanks for showing ua the way to understand better this issues.

Can you please tell us , in what tests did you strongly based to set those voltage settings?

I'm trying for along time setting voltages but somehow sometimes i get some mini freezes changing between aplications pages, or somethings like that and i'm guessing it's because of my settings but i'm not really sure.

I believe the phone use to be more fluid somehow. Could this be because of the settings i have?
[Galaxy S II General] cykalu:
800 mV is the minimum.

Ref : http://xdaforums.com/showpost.php?p=16833818&postcount=1983
[Galaxy S II General] chrisjcks:
I see,

But setting 600mv in setcpu shows 600mv as current and saved voltage - thats why i asked.
[Galaxy S II General] chrisjcks:
Ive found the best test is to adust 1 value per day, use your phone as you usually would throughout that day. Do reboots, gaming, browsing and use as many apps as possible.

If no problems, knock that value down by another 25 and do another full day real-test.

You could speed it up and do 2-3 values a day, just depends how much you use the phone and how much you test that voltage.

Simple speedy guideline test:

Use performance profile, if your testing 1400mhz, set your cpu to 1400mhz/200mhz (obviously)

Ive found that putting your phone into deep sleep and a simple wakeup is a good test, most incorrect voltages will crash here.

If a crash happens, reboot and knock it up one notch by 25mv, this is your guideline voltage for this freq.

Once you get your guideline voltages, apply them all (not on reboot) and run it for a day... 2 days...3 days - you will know if its stable enough after a few days. (then you can apply all on boot)
[Galaxy S II General] KennyLegend:
If anyone could advise here id be grateful.

I uv 'd my S2 by 100mv on every step with setCPU last night. I left governor at ondemand .

Viber crashed on me while ago and gave me the "Viber just crashed" message. After that the screen went off and phone got hot.

Anyone know what voltage step id need to adjust to right this?
[Galaxy S II General] chrisjcks:
Every phone is different, did you just jump straight to -100mv on each step freq?

Id start with -25 on the highest freq alone. (performance profile)
[Galaxy S II General] KennyLegend:
Yeah I did . Forgot to mention I'm on ninp 2.13 kernel.
[Galaxy S II General] chrisjcks:
You cant just adjust each freq. by the same value.

Start with the highest freq you wish to use (in my case 1400mhz)

Use performance profile at the speed your testing, this will keep it at that speed.

Adjust it by 25 (1350mv > 1325mv)

Apply it, then use your phone for gaming, browsing etc throughout the day. Also Let your phone go into deep sleep and then unlock/wake up your phone.

Only when your happy it can perform everything inc games that you throw at it, lower it by another 25

Only do one freq speed at a time, dont rush it and dont assume you can lower one by 100 so you can lower another freq by the same, it doesnt work like that :)
[Galaxy S II General] rab1412000:
OP, please include an undervolted ragemod 1.1 in your comparisons

TIA
[Galaxy S II General] KennyLegend:
Thanks a lot for this advice.

Unfortunately for me I Don't think I have the patience for that though. It would take me two weeks to find stable values at that rate. ..lol

I suppose I could give it a go....... considering ill have this phone for another 18 months, 2 weeks testing isn't too much to ask.