yashsingh1/xdaforums huggingface dataset:
[LG Optimus 2x] spica1234:
Ferrum thats what said by compiling kernel with higher debug and kernel message printing for my testing to know exactly whats responsible for battery consumption.. What i found many loopy RCU calls and such wakeup processes. I have been trying to fixing it in SR4. By modifying RCU calls to be lazier cpu can reach and stay very soon in idle stage.
[LG Optimus 2x] SuperSkill:
[/COLOR]Actually, making an app like that should be very easy. Just found my next project. A CPU battery eater. Could record how long it's been running every second or so.[/QUOTE]

An app like that are welcome indeed Trym :)
[LG Optimus 2x] TrymHansen:
I just want to clarify that there were two debates going on here, unrelated.

1) Spica's claim that an undervolted CPU runs slower.

2) Does undervolting save battery?

Now Spica has specified that he didn't in fact mean the CPU runs any slower, but that it somehow uses lower frequencies when undervolted. (Since he still claims any task takes longer when undervolted.)

@bvhoesel - you are entirely correct. The test should not be regarded as scientfic (I called it slightly unscientific, perhaps better to say majorly unscientific), but it should still give a pointer as to whether any (perhaps non-existent) gains are enough to bother with undervolting. (Don't get me wrong, I'm not advocating undervolting at all, never use it myself, but it is still a topic of great interest for many users.)
[LG Optimus 2x] Ferrum Master:
Simple method? Multhithreaded PI calculation, and how long the battery will last. But we need an app for that... maybe there is one...

Of course... we can cheat, and make a battery threshold... in what time we can drain 0.1V from the battery. It is a quite lot actually. And the compare always should go from 4.2V max level as battery discharge voltage graph isn't quite linear.

Then we can run tests in various max frequencies and limit it to example 800Mhz, that will give a reasonable battery boost really.

---------- Post added at 09:52 PM ---------- Previous post was at 09:49 PM ----------

It shouldn't.

It seems nvidia has hidden some presents underneath it's layer. Hidden throttling... or I'd like to say brownout protection? It has a additional code to prevent sag, because of the voltage level and throttles down the freq to ensure the current will be sufficient? Trym? It could be it? The only reasonable explanation that could prove this statement right.
[LG Optimus 2x] spica1234:
Trym again bro. I dint said about lower / max freq that was just an example that if we have undervolted every freq to -100.

Originally posted by spica234

"As i said earlier an undervolted cpu will take more TIME to finish task"

Let me explain again if cpu running at adequate frequency is taking 'x' amount of time in seconds/ms/ns to finish A task then a cpu running undervolted will take more time to finish same single task. If time taken by an undervolted cpu is 'y' to finish same task than y>x for same task.

I talked about it under our phone case.
[LG Optimus 2x] TrymHansen:
I'll make one. I'll borrow some code from either SuperPI or Linpack, run it in a loop and record the time periodically. Upon next boot we can see the total runtime. Can't promise it'll be today or tomorrow though.

My thoughts exactly. It seems very strange, but I cannot prove it is not so. I have not experimented a great deal with undervolting, but I'd be very surprised if it were so. I have not seen any variances in cpu-scaling this far, but then again not done any proper tests.

---------- Post added at 09:00 PM ---------- Previous post was at 08:57 PM ----------

Ok, I'll bite. What makes it run slower? Does it run at a lower frequency? Or does it perform tasks at the same frequency at slower rate? It has to be one or the other.
[LG Optimus 2x] Ferrum Master:
I can give an explanation why such brownout protection is introduced.

Engineering wise it loosens up the demand for high precision voltage regulators, so the overall BOM cost goes down for each unit, as the CPU will work stable from unreliable... sagging and wiggling voltage regulators... as it has a protection against it - quite nice move actually from nvidia i cannot blame them for that. I can bet that thing is borrowed from engineering GPU stuff.

---------- Post added at 10:05 PM ---------- Previous post was at 10:01 PM ----------

Trim a example for a mere mortals like us.

Imagine a bottle of beer and a bottle of milk... it usually has higher diamerter neck.

So... our task is to fill up that glass... Milk has an overclocked bigger hole... and we can pour in it faster than our beloved beer... (going to fridge NOW).
[LG Optimus 2x] spica1234:
No it doesnt run at lower frequency it runs at same frequency scaling like a cpu running with adequate voltage.

Low voltage will create a lag in cases atleast of mobile. And thus it will take longer time (not much but slight) to execute-finish same task by an undervolted cpu then an adequate voltage supplied cpu.

And in some cases when its been undervolted too much , during execution of task if sufficient voltage is not being supplied ( in our case to cpu ) due to undervolting we will face freeze/kernel panic. Needing a battery pull.

Nvidia i guess has by suficient testing have selected these voltages.

In simple what i was talking was.

If for example we run quadrant advanced app and do benchmarks with -100mv undervolted then the total time it will take to finish quadrant benchmark test is more time than a cpu running at sufficient voltage takes to finish same quadrant test.

This was just an example i gave as a TASK.
[LG Optimus 2x] TrymHansen:
But we're not talking about overclocking or underclocking, are we. We're talking about undervolting and if that makes the processor run slower. As you say, the only reason it could be so is due to throttling of some kind.
[LG Optimus 2x] maxbaron:
I'm unlucky: bsod every time the phone went in standby for more than 5mins with last betas. Deleted all 3rdy part scripts and no powersave. Any suggestions?

Inviato dal mio LG-P990 con Tapatalk 2
[LG Optimus 2x] TrymHansen:
So now you are again saying that tasks at the same frequency runs slower when undervolted. This goes against pretty much everything. Now, Ferrum has a point, there might be some protection built in which lowers the frequency, but then it's not running at the same frequency, is it?

I still maintain that any given task running at <insert random frequency> will finish in the same time, undervolted or not. This is so obvious it's very hard to see why there'd be any debate about it at all.
[LG Optimus 2x] spica1234:
Thank u for reporting which tb you are facing this issue with?
[LG Optimus 2x] SuperSkill:
Weird........you must be alone on this now....haven't had a freeze since pre otf rc12 :)
[LG Optimus 2x] Ferrum Master:
Yeah... thats how we understand also and is a true possibility of that kernel panic that Spica says.

But Spica has an additional argument... he is right about the fact, that overclocked CPU will calculate that number of desired pi length in faster time.

The question is... the saved time is enough to compensate overclocked additional curent draw delta between stock maximum draw.

---------- Post added at 10:20 PM ---------- Previous post was at 10:18 PM ----------

No SuperSkill... I've PM'ed a lot Spica... I also also suffer from BSOD while using OC. Now testing at stock speeds again... it seems there is still an OC code problem.
[LG Optimus 2x] spica1234:
Uff confusion again

What i am saying is that suppose you have undervolted every freq to -100mv.

Then with this uv of -100mv if you are running a task for example a quadrant standard application for testing benchmark then it will take longer time to finish this test then a test being run by a cpu which is not undervolted.

That was an example of task execution. And the TIME i was talking about .

Thats it forget cpufreq scaling i am not talking about it now nor i did in the past only TIME, TIME & TIME

:)
[LG Optimus 2x] spica1234:
Ok gn guys have fun:)
[LG Optimus 2x] TrymHansen:
That's back to batterylife again. No, it will not. Disregarding display-power, baseband-power and wi-fi power used during the task, the faster the frequency, the quicker you use the battery. At the same voltage-step, the energy used is the same for any given task, but it will be spent quicker at higher frequencies (frequency and time cancel each other out). At lower voltage steps the efficiency goes up, even if the time goes up. (I once made a post in the Topogigi thread where we calculated the relative differences between the speeds and the voltages in the voltage table, using the regular CMOS power-formula. It may not be correct for Tegra2, but still a pointer.) At 389Mhz it used 64% of the energy for the same task at 1015 Mhz, although it of course took 2.6 times as long.)

If we're talking about real power-use we need to know how much power the rest of the components use over that additional time.
[LG Optimus 2x] maxbaron:
Last attempt was made with the version downloaded some minutes ago.

Inviato dal mio LG-P990 con Tapatalk 2
[LG Optimus 2x] maxbaron:
Last attempt was made with the version downloaded some minutes ago.

Inviato dal mio LG-P990 con Tapatalk 2

Inviato dal mio LG-P990 con Tapatalk 2
[LG Optimus 2x] bvhoesel:
If I understand spica reasoning well then it is in simple terms the following. (I am not a knowledgeable hardware guy but did have had some basic electronics calculus at high school.)

The hardware we use is still composed of resistors and capacitors, however small. Capacitors need a certain amount of electrons to get charges to represent 1 or 0 (bit). With lower voltage it takes longer to get the needed electrons 'in place' thus it takes longer to 'charge' to 1. One processor command involves a lot of bits changing. As a result it takes the processor longer to complete the 'command'. And if it takes to much time (as compared to the current frequency set) the processor will crash because it's state becomes unstable.

---------- Post added at 09:44 PM ---------- Previous post was at 09:37 PM ----------

Sound similar to mine problem. Have you tried overvolting (system tuner app can do that)? Works for me.
[LG Optimus 2x] Ferrum Master:
More or less I have the same problem... There is no help really... :D The phone simply freezes at random moments when sleeping, and never when I torture it at max frequency 1.4Ghz :D

I am testing it at stock speeds now... if not... i have to make a betrayal(nandroid backup) to Stefan's camp in order to survive the night :D.

@Trym

Yes you are completely right. Despite the thing Tegra is not a plain CMOS but a SoC that complicates everything... But shouldn't drastically change the math in this example. Yes I've said this earlier and forgot. Lover voltage the lover is the current leakage and thus higher efficiency. And we have too many unknowns because of nVidia. BTW I've reading One X formus also sometimes... ohhh one hell of a device... same problems regarding nvidia attitude... same mature content words etc... :D
[LG Optimus 2x] bvhoesel:
Did you try overvolting? I am facing the same problem as far as I can see. +25mV (on all frequencies) works for me.

It seems I am not the only one with this problem after all ;) .
[LG Optimus 2x] TrymHansen:
If a task uses MORE TIME, it must run at a SLOWER SPEED. You speak is if the TIME and FREQUENCY are completely unRELATED.

Look ABOVE.
[LG Optimus 2x] bvhoesel:
The task may run at lower 'experienced' speed but the processor run at 'requested' speed. I do not know the processor specs but most modern processors are able to skip (or lose) clock cycles to wait for commands to complete. As long as the loss is within 'reason' the processor can cope with it. This might explain what spica is talking about. In this way frequency and time are not that fixated to each other as you might think.
[LG Optimus 2x] tablighs:
With all due respect to all Gurus here, sometimes I cannot help it but to think some miscommunication arises here are caused by language barriers.

We need to understand that some of us are not native English speaker and may not excel in it. Although one may posts something here in English, it may not 100% translates what is in the writer's mind.

It's better if we help out each other to clear out vagueness in explanations, especially those technical ones that I'm sure only a few here can actually understand, so that instead of shooting down each other, we can actually progress much faster and everyone will benefit from it.

I am one of those who does not understand much of these technical debates, my contribution is just mainly to test out new releases and if there's any problems, I will report it.

If you ask me if UV makes my device runs 'slower', I will say yes. Before, I like to undervolt my device in the intention of saving precious battery life and I found out that the overall experience is abit sluggish. But this is basically my gut feeling, no scientific prove. so you can take it with a pinch of salt. :D

Cheers everyone! :)
[LG Optimus 2x] TrymHansen:
This is identical to the first claim I wanted verified. I find this ... not easy to believe. You're suggesting that at a set frequency we have a variable speed-processor depending on the voltage we feed it, because it will wait for electrons to arrive at the gates, so to speak. To use laymans language I find that particular idea bonkers. Failure is always an option I guess, so if I'm wrong, I apologize in advance.

You're right of course.

...or you have experienced what you did because that was your expectation. "Feeling" how fast/sluggish a device is is a completely useless metric (as you say, the pinch of salt here is rather large.) Just look at the number of posts claiming they get/got much better batterylife by "calibrating" it, or that images on the phone were much better with the "Bravia" tweak. We're subjective beings with subjective and easily influenced perceptions.

I do not intend to start a war over anything here, but it is not enough to simply claim (and this is not directed at Spica, but to everyone except tablights, who put in his disclaimer) something, it needs to be backed up by measurements and testing. These forums are full of "Dramatic increase in battery-life", "Revolutionary smoothness" etc. If all those claims were true we'd have devices 10x times as fast AND with 10x longer battery-life than a year ago. Again, not directed at Spica.)

I see I'm suddently into a "wall-of-text" territory here, so I'll finish with this:

I apologize to Spica for posting what I realize must have seemed like a personal attack, that was not the intention. The objective was to verify, if possible, that that particular piece of information was verified and tested.

I apologize for hogging the thread, to everybody.

I'll go away now. In a few days I'll have a simple app ready which will measure two things: How much work can be done in a set amount of time at a given frequency (until now this used to be a constant), and "How long can it work at a given frequency at a given voltage." People can then adjust their own voltages and see for themselves what is, in fact, true. Again, this will not be purely scientific, but a lot better than "it feels like..."

Sayonara.
[LG Optimus 2x] slyzzz:
Mirror

Is there a mirror for the latest kernels? Error 401 for dropbox. I cant download. :(
[LG Optimus 2x] Ferrum Master:
Mates mates... chill down...

Trym and others. I would like to say. That our current kernel is broken anyways... so nothing to do. So this chat is quite useful to our experience and overall empiric education.

And the last thing... you'll see in the image. The text says -Not this down below, but the that one on right on our tables now like in my example on my table at home:). It is sunday -chill out mates.
[LG Optimus 2x] baltac:
You could simply add the number of GPU cycles, related to the number of transactions completed in the amount of time at a given combination of voltage / frequency.

I try to explain my thoughts better.... My experience of overclock / overvolt, is limited to the PC's GPU, and I remember that:

-If you Undervolt you can have minor GPU heating, but with too much UV, you might incur in a loss of frames, due to errors in the computation of datas, which lose their consistency, and that the CPU has to recalculate losing a certain number of cycles. And more is the UV and more are the lost data (and you can have lags and freezes).

So if with the same freq, in a minute you can have (for example) 10000 frames at standard voltage (or with a low UV), if you undervolt too much, in a minute you'll have (for example) 9500 frames. Or in other words, with the spica's pov, to have 10000 frames you need more time... This could be comparable to a delay in the execution of a task.
[LG Optimus 2x] fuxmen:
sr4 test ->

2h of doing almost nothing and 4% drop is it good? WIFI allways on, Will see after second charge, because for me it should be more like 1-2%
[LG Optimus 2x] spica1234:
Alright cheers trym. My intention was not to hurt.

Anyways guys today, SR4 will be released. With some of blocked unneeded never ending RCU calls. I am not gonna claim it will give you more battery life. But you will report the same.

Then RC project will be resumed for stock with kernel 3.0.30. Periodically SR series will be implemented with stable 2.6.32.9 series:)
[LG Optimus 2x] LGXX:
Just happy!

3G always on, usage statistic -> look at the blue bars

Gesendet von meinem LG-P990 mit Tapatalk
[LG Optimus 2x] fuxmen:
wchich BB do U use?
[LG Optimus 2x] spica1234:
Thats what i'd like to claim for:) best stock battery life:)
[LG Optimus 2x] spica1234:
Allow one cycle of battery for a stabilization of result:)
[LG Optimus 2x] Memhis:
I must report that I have experienced a lots of sod`s and I must go back to SR3 or Gueste. First day of using it have been only one sod (when I was on TeamViewer), but second day it have crashed a lot doing nothing special on phone. Battery is good.
[LG Optimus 2x] slyzzz:
Error

I cant download right now. Dropbox error 401. Inactive files already.
[LG Optimus 2x] spica1234:
HP_PreSR4_Final_Preview_UID_FIXED:

Those who have had issues of SOD/BSOD Please try this:

Just report of SOD/BSOD not smoothness, smoothness is very good as we know already:) So I can start finalizing remaining stuff for SR4 public release:)

It has been compiled with latest GCC-4.7.1 with ARM Multi-Thread simultaneos optimizations ( http://ieeexplore.ieee.org/xpl/log...re.ieee.org/xpls/abs_all.jsp?arnumber=982682 ) for more quicker application responce and more adequate gaming eXperience and it has been Optimized for better cache-prefetching control.

Very first 2x Stock Kernel supporting ARM Multi-Thread Optimization.

CAUTION: High-PERFORMANCE & Heavy-Duty battery life ahead!

It found working flawlessly with even Stock LG Launcher:)

Download:

(Thanks to Kornunuma)

http://www.xdafileserver.nl/index.php?dir=LG/Optimus 2x (P990)/roms/Horse Power 2x eXtreme
[LG Optimus 2x] slyzzz:
v20q

Is this compatible with v20q?
[LG Optimus 2x] spica1234:
Yes compatible with any Stock-GB Roms:)
[LG Optimus 2x] Ferrum Master:
Stock rom... of course... You should read more around.
[LG Optimus 2x] spica1234:
After install through recovery Please Fix permissions as well through recovery:)
[LG Optimus 2x] mastermind88:
Just flashed. The phone freezes after the boot. Stock ROM gingerbread v20q
[LG Optimus 2x] spica1234:
Have you tried fixing permissions through recovery?
[LG Optimus 2x] mastermind88:
Yes, i've backed up my system, cleaned Dalwick Cache, flashed the kernel and fixed permission. I've tried to flash two times with the same result...the phone freeze after boot.
[LG Optimus 2x] zaldax:
+1, i had same problem
[LG Optimus 2x] spica1234:
Wait 5-10 mins. Its uid issue:) i am reuploading:)
[LG Optimus 2x] ckjwee:
Installed.....Loaded ok... monitoring....

Homero v1.4.0

Hp_PP v9 modified by Flix

Hp_ SR4_review final

edit: Got freeze after WIFI Off

Remove battery, power up

On Wifi ... not able to open browser

Going back to resolve back to

Homero v1.4.0
[LG Optimus 2x] Flat-Eric:
My phone freezes after the boot, too. But i've removed Batt and tried it again. Second time it works. :)
[LG Optimus 2x] SuperSkill:
Battery

Hi:)

I did a full charge(last test build before HpSr4 Final Rewiev,dl that now). I want to share 2 pictures of battery consumption. I never had this good battery before. As I flash much these days I use a cheap DealExtreme battery(around 5 USD),Setup: DjangoManouche 1.3 Beta 6, Kernel mentioned, I also want to thank my friend Spica for his knowledge, patience, his ability to work hard and service to all users:
[LG Optimus 2x] spica1234:
Hp_pre_sr4_preview_final_uid_fixed

Hello,

guys fixed UID issue. Causing freeze:

Link Updated:

Download:

http://xdaforums.com/showpost.php?p=25493946&postcount=4888
[LG Optimus 2x] spica1234:
Yes, I know myself how hard I've worked for PowerManagement with my knowledge and experience. Sorry if it hurts for very FEW ppl But This SR4 will deliver the maxium battery life on stock kernel. Because when I claim for something I mean it, When there is REVOLUTION only, than only the word REVOLUTION has been used, not every now and then:). I dont use word REVOUTION here and now often just for NOTHING:) The word has much heavier value:p Word REVOLUTION was originally bornt with OTF before some months and still being popular with every versions of HP :p ;)

Sorry If it hurts , It's SAD, STRANGE but the NAKED TRUTH that I can claim this kernel to be the most long lasting battery life providing kernel for Stock ROMs:) Cause I myself know how hard I've worked for this. And that's most users' appreceation not very few ppl's bash, who makes me continue the REVOLUTIONs( As even since the BETA of HP Krnl to this stage, every version stands for never seen, never heard features, never introduced before) to bring to the LG Optimux 2X:)

Please test this latest UID Fixed version, So I can finalize some changes and publically release Smoother,Faster, Stable and the most long battery lifed SR4 kernel:)
[LG Optimus 2x] kosi2801:
I'm very curious to try this one out, but I've got too little time right now. Just one question, will you update your changes also to Github?

Keep up your great work!
[LG Optimus 2x] ckjwee:
Reinstalled fixed UID updates

sofar ok no freeze,

Will monitor......

Thks .....
[LG Optimus 2x] spica1234:
Yes ofcourse. That will obviously help other developers:)

I believe in this:

"IF NOBODY SHARES ANYTHING THEN WE COULD HAVE NO FURTHER DEVELOPMENT WHEN ESPECIALLY ITS OPENSOURCE"

"SHARING IS THE LEAD KEY IN AN OPENSOURCE SYSTEM"
[LG Optimus 2x] SuperSkill:
Exactly mate :) Love your entusiasm :* well deserved recognised developer, well deserved donations, i hereby encourage you all to donate, spica are the one giving us revolutionary kernel news, all others deliver very good to, but spica;I've stocked to your kernels 99.99999 since first release and it'll stay this way for me(it was a hard time for pre rc12 first OTF, but it was a pleasure to help you to get in goal and achieve rec dev) , you have my honor now and forever. Sometime in the future you will change device, let me know then so I can keep walking your road :D
[LG Optimus 2x] spica1234:
Guys please report SOD/BSOD issues for them who have had it in the past:)

If not reported any fpund bugs, SR4 will be released within 24Hrs anytime:)
[LG Optimus 2x] carburano:
Pre Sr4 is with me in Barcellona... Very good job as ever friend!

Sent from DjangoManouche!
[LG Optimus 2x] Memhis:
Using it 1.5h, from when you have uploaded the fixed version. Waiting for freezes /bugs to report, but there is nothing :). All is working for now, will report if I find something. (My freezes problems have showed after 24h of using the last preview version).

I am thankful for all hard work that you have done, keep it up.
[LG Optimus 2x] spica1234:
Welcome bro Please report battery experience too:)

Sorry for delaying your 1.3 release uptill now. But within 24Hrs max SR4 will be released:)