yashsingh1/xdaforums huggingface dataset:
[Nexus 5 Original Android Development] Sharky444:
I'm using this kernel since around V53 (purchased the FKU app).

53,54, and 55 were rock stable, not the slightest problem.

Updated to v56 with Autoflash. After boot I see the launcher for about 20-30 second, then the phone reboots.

Happened 5 times in a row.

Then I've restored the v55 kernel (needed 3 tries, because of the reboots) and all is fine again.

No over/undervolting used. Default Google ROM with Root. 32GB Nexus 5, European version.
[Nexus 5 Original Android Development] tmihai20:
I always clear Cache and Dalvik-Cache after flashing a new kernel and I didn't have any issues. I don't use any other mods, just stock 4.4.4 (at the moment) ROM and Franco's kernel.
[Nexus 5 Original Android Development] RobLudo:
Why do you wipe dalvik?
[Nexus 5 Original Android Development] eseregin:
UV does decrease power consumption for CPU. Lower current with same volts will give you less power consumption.

UV does not really improve battery life simly because the main power succer - Screen! Not CPU... So why even 10% , 20% decriase of current will give you may be at best 1% better battery life... So it probubly does not worth to UV... But everyone will decide for himself 8-)
[Nexus 5 Original Android Development] Technecium:
Here we go again. Coke vs Pepsi, Windows vs Linux...
[Nexus 5 Original Android Development] Sharky444:
Why? They are not related to the kernel whatsoever.
[Nexus 5 Original Android Development] RobLudo:
No fight, seriously, i was just curious to know why he's doing something I think it's not useful. And maybe avoiding to make it happens again, because reconstruction of dalvik is onerous.
[Nexus 5 Original Android Development] tmihai20:
I believe Franco suggested it. I do it so the existing apps don't misbehave.
[Nexus 5 Original Android Development] Technecium:
Fair enough. There's valid arguments to both and this thread has seen its fair share of them.
[Nexus 5 Original Android Development] Bronto9:
I'm not using the app, but on my phone screen casting works flawlessly
[Nexus 5 Original Android Development] sjknight413:
Can't believe there is still a misconception about that you should wipe the dalvik cache before flashing a kernel. It's a totally pointless exercise as the dalvik cache is COMPLETELY unrelated to the kernel.
[Nexus 5 Original Android Development] fatspirit:
Unchecked legacy knowledge (:
[Nexus 5 Original Android Development] tmihai20:
OK, I won't do it next time. I know Dalvik Cache is related to the apps, it was indeed legacy knowledge. But I think clearing Cache doesn't hurt.
[Nexus 5 Original Android Development] RobbieL811:
It doesn't hurt anything to do it, it's just not needed. Anytime I ever flash a kernel through recovery, I just flash it then fix permissions & reboot.

Sent from my Nexus 5
[Nexus 5 Original Android Development] Sharky444:
Dalvik has nothing to do with the Kernel.

Why fix permissions?
[Nexus 5 Original Android Development] Hopper8:
Another old wives tale for you then... I thought that fixing permissions didn't do anything on KitKat? I could be wrong on that, I just read it somewhere on the forum.

Sent from my Nexu5
[Nexus 5 Original Android Development] Aerowinder:
Old habits die hard. I still wipe Dalvik anytime I flash anything.

For the record, I know that it isn't necessary.
[Nexus 5 Original Android Development] armymax:
When the cpu throttles it will not back to standard frequencies even if I wait some hours in deep sleep. Is it normal?
[Nexus 5 Original Android Development] The Gingerbread Man:
Can you get a proc/last kmsg? That will show us the error you are experiencing. Or maybe when you can boot to android Os wipe fku data and reboot manually quickly

---------- Post added at 12:55 PM ---------- Previous post was at 12:54 PM ----------

Your wasting your time. No need to wipe anything here, only the drool off our chins when there's a new release!

---------- Post added at 12:56 PM ---------- Previous post was at 12:55 PM ----------

Your wasting your time. No need to wipe anything here, only the drool off our chins when there's a new release!
[Nexus 5 Original Android Development] der_sascha:
i get also reboot after flashing kernel

i am using vormer tweaks script no undervolting
[Nexus 5 Original Android Development] Free4ever2:
I had the same issue. Turns out that if you have Viper4android zip installed through recovery, it causes Google Play Services to crash. I only figured this out after trying a whole bunch of things.

I've tried freezing and uninstalling Viper4android with Titanium Backup, but it didn't help. Only way I found to get screen mirroring to work is to flash rom back to stock, and not install Viper4android as a system app. Hopefully there will be an update to resolve this.
[Nexus 5 Original Android Development] Theberge43:
I had same exact problem, bunch of force close and reboot.

Reverted back to 55 for now.
[Nexus 5 Original Android Development] Enddo:
post a last_kmsg log if you actually want to contribute to getting the issue fixed. if not, it will take much longer to fix, and might not get fixed at all
[Nexus 5 Original Android Development] aimcr7:
I don't have that issue, I always flash viper4android 2.3.3.0 zip after updating the rom and never had such issue.
[Nexus 5 Original Android Development] armymax:
Random reboots with r56. UV -50 PVS 3 http://pastebin.com/V1arqfKY
[Nexus 5 Original Android Development] fredfox_uk:
Remove the UV and try again. Lots of reports of issues with R56 and UV, in fact pages of it.
[Nexus 5 Original Android Development] armymax:
It also throttles very often and it does not return to standard frequencies even if I wait hours in deep sleep. Is this normal too?
[Nexus 5 Original Android Development] treehugger38294:
Reboots with r56 as well. Reverting to r55.
[Nexus 5 Original Android Development] odavans:
That's your problem, I have no reboots or any lags with r56
[Nexus 5 Original Android Development] justibasa:
My God people, if your having reboots then stop undervolting and then complaining here. It's getting to be a little repetitive and a bunch of bullsh&$. There is no fracking reason to report your reboots if your uving.
[Nexus 5 Original Android Development] fredfox_uk:
.....and, if you do get reboots without UV you could at least try to help by posting a log.
[Nexus 5 Original Android Development] PetritH:
im on - 75 across the board, 300Mhz at 625 no reboots so far
[Nexus 5 Original Android Development] donwhall70:
I wipe dalvik so that people will ask me why I wipe dalvik.
[Nexus 5 Original Android Development] Red5:
Im -uv by -50 across the board, PVS1 and I have not had any reboots yet.
[Nexus 5 Original Android Development] ironjon:
Did you mean 675 at 300 right? :confused:
[Nexus 5 Original Android Development] Free4ever2:
Do you have the Chromecast? My post was about issues with using Viper4android with Chromecast's screen casting feature.
[Nexus 5 Original Android Development] aR_ChRiS:
Or just simply revert the voltages to stock.
[Nexus 5 Original Android Development] peikojose:
Getting rebootz only UVing -200 all frequencies.

Plz franco fix it asap

jk
[Nexus 5 Original Android Development] PetritH:
I seriously meant 625 :)
[Nexus 5 Original Android Development] ironjon:
Incredible, mine at 700 reboots sure.

Yeah I know there are different PVS but a difference of -100 is a lot.
[Nexus 5 Original Android Development] PetritH:
At beginning I was surprised too.. haha
[Nexus 5 Original Android Development] Tzfardaya:
Mines rock solid at 600..
[Nexus 5 Original Android Development] supernova_00:
Wiping dalvik IS the problem, should be wiping ART! ;) Is there even an option for that?
[Nexus 5 Original Android Development] Tzfardaya:
Well, if you really want to wipe Arthur... I could introduce you.. But I know he will think you're... Um... Odd.
[Nexus 5 Original Android Development] nldxda:
Black screen.. R56, stock 4.4.4 xposed

http://pastebin.com/pT6vcCjZ
[Nexus 5 Original Android Development] Codekrypt:
Using r56,whenever I charge my phone I'm getting erratic touches and thus always end up entering the wrong pattern or clicking a wrong app. Anyone else? Also franco if you need any log or something let me know please. Thanks :)
[Nexus 5 Original Android Development] Tzfardaya:
Undervolting? Non stock drivers? Xposed?
[Nexus 5 Original Android Development] Codekrypt:
No mate, underclocking to 1574 though.
[Nexus 5 Original Android Development] Tzfardaya:
Undercooked shouldn't cause that... Third party charger (or dying charger, or dying cable might though)
[Nexus 5 Original Android Development] Codekrypt:
Non stock charger, stock cable. Flashed r56 today n got that charger today. New charger so I don't think it'll cause problems. Sure about this? Any reasons? Thanks.
[Nexus 5 Original Android Development] franciscofranco:
That's it I'm gonna remove UV. Cry all you want, I won't care. If you're having reboots but you're not undervolting then fúcking post some logs. I had r56 on public tests for over a week...

Hmm.... I have no clue. I need to check again.

Alarms code is unchanged. With r56 try not to UV.

What about a log? I'm not a magician.

I never said such thing...

It returns back to standard frequencies alright. I did my share of stability check runs forcing it into throttle, then back out of throttle and it's fine.

That happens since stock, since the device was released. I think it's something in the touch firmware.
[Nexus 5 Original Android Development] Codekrypt:
Ohh, Damn. Something which cannot be fixed by you is it? It's ridiculous that they haven't fixed it yet. Sigh
[Nexus 5 Original Android Development] DryEagle:
I have quite weak wifi signal (usually 1-2 bars out of 4), and about 10 things on my wifi network. and a lot of time I get programs just unable to connect to their networks etc (e.g. twitch tv, some games that sync save online, etc). I am currently on westwood tcp algorithm based on someone's suggestion in this thread, but, would using one of the other ones perform better for me? I don't know what any of them are about, so maybe someone can suggest what's better in this scenario, thanks
[Nexus 5 Original Android Development] Enddo:
it's been fun guys. time to look for another kernel
[Nexus 5 Original Android Development] Dungeon47:
But... but... my placebo! http://media3.giphy.com/media/cAaTcA2OxFtao/200_s.gif
[Nexus 5 Original Android Development] franciscofranco:
No I cannot fix it.

The TCP algorithm is unrelated to that.
[Nexus 5 Original Android Development] Clauu:
Let's clarify some things, till r56 i could easily globally uv with -75(max freq to 2.0ghz) and now i'm also having random reboots so more likely the new test image has some little uv by default or other critical thresholds changed so stop being silly blaming uv for these reboots since until now uv was just fine. Instead you should better increase voltage by small values like +5 +10 etc, for me at least +5 did the trick
[Nexus 5 Original Android Development] Chaplan:
[MENTION=3292224]franciscofranco[/MENTION] R56 is draining 3% battery per hour with no use at all. I don't care about undervolting, i just use stock settings.

I would like to go back to R54. Can i flash it over R56?
[Nexus 5 Original Android Development] Tzfardaya:
Yay

---------- Post added at 01:14 PM ---------- Previous post was at 01:14 PM ----------

Bye

---------- Post added at 01:16 PM ---------- Previous post was at 01:14 PM ----------

No, once you update you're locked in, you can't even go back to stock...

just flash 54 over top, same way you flashed 56...
[Nexus 5 Original Android Development] 3dawg:
I've always wiped dalvik and cache. For the first time, I went from r55 to r56 with no wipes. Play store crash, chrome crash, full system crash. Then it boots back up and I find that it's reverted to dalvik from ART.

Wiping dalvik cache + cache is still necessary for a totally problem free flash imo. Ignore the people saying it's useless. Before today, I've read through thousands of posts over the years from people having problems when upgrading/flashing things and I've always thought "why does everything always work no problem for me? How come I never have any of these issues?".

Well now I know why. Stop telling me not to wipe cache when clearly not doing so is related to more problems/errors.

EDIT: Unless it's related to r56 somehow?
[Nexus 5 Original Android Development] Chaplan:
Where can i find this?
[Nexus 5 Original Android Development] Wenzo2:
Nope... That has been fixed since 4.4.3...
[Nexus 5 Original Android Development] sjknight413:
Everything you just said is a compete load of rubbish.

Through my four years of android hackery I have never wiped the cache or dalvik cache upon flashing a kernel and guess what? I've never had any issues. You will not get any problems if you don't wipe the caches when flashing a kernel because they are COMPLETELY UNRELATED.

whether you think they are or not is irrelevant because it is a stone cold fact (and indeed to some extent common sense) that the kernel and dalvik cache are in no way related.
[Nexus 5 Original Android Development] 3dawg:
Well in that case, R56 totally ****ed my rom. After trying to go back to ART since it forced me back to dalvik, my data was lost somewhere in the process.

EDIT: Nvm, I spoke too soon. After another reboot, it all seems to be back. This is the weirdest upgrade I've ever done.
[Nexus 5 Original Android Development] akash3656:
All I got to say to you is this: K

And this: Cool story bro

And: Have more fun with rebuilding ART cache on each kernel flash. Which adds up to 10-30 minutes.
[Nexus 5 Original Android Development] der_sascha:
56 works now without reboots after flashing again
[Nexus 5 Original Android Development] simonarturo:
Someone correct me if I'm wrong, but it has been stated in this thread before that idle drain is not kernel related, instead it has to do with wakelocks and signal strength.
[Nexus 5 Original Android Development] bcote311:
R56 running flawlessly with incredible battery life. Thanks Franco!
[Nexus 5 Original Android Development] Chaplan:
you can state what you want. R56 is the culprit on this drainage. Same network, same rom, same apps, same greenify, only kernel changed... 3% is very noticeable in one our. Never happened before, to me at least.
[Nexus 5 Original Android Development] 3dawg:
You're the funniest person on XDA. Someone give this guy a medal.

Don't quit your day job mate.
[Nexus 5 Original Android Development] Technecium:
I don't think these were ever pushed to nightlies repository, but there were some links posted last week to another repo on github.com. You'll have to get them from there.
[Nexus 5 Original Android Development] simonarturo:
Then seeing as you already 'diagnosed' the issue, you could just try with stock kernel or a different kernel to see if the drain still happens.

My bet is that it will, but you might get lucky, who knows.

As for me, the only time I leave the phone idle for more than 30 minutes is when sleeping and so far my drain has been tolerable (around 1% per hour with the phone in sleep mode).

Bear in mind that each phone behaves differently. It could be that an update or xposed module not playing nicely with kernel changes, etc is causing the issue here.
[Nexus 5 Original Android Development] fredfox_uk:
Good advice.
[Nexus 5 Original Android Development] Ryrynz:
I just turned on my N5 from deep this this morning and connected via WIFI, had Play store and Instagram "stop working" in the background, something is up with R56 I think. Never had a single problem until now.
[Nexus 5 Original Android Development] Chaplan:
I don't use Xposed (hate the dam thing), tested with stock and code_blue witch derives from Franco. No drainage there. And i have not diagnosed the issue. It is what it is. I will go to R54 and keep informed here.
[Nexus 5 Original Android Development] ColdFire InOx:
r56 completely f***** up my phone. Everything crashes and now I can't even flash the previous version, neither through fastboot or adb.

Update: Had to completely reflash 4.4.4 in order to get my phone to work.
[Nexus 5 Original Android Development] Dungeon47:
I always keep a zip of the last version in my storage just in case. Good habit to have.
[Nexus 5 Original Android Development] 3dawg:
Nice to see I'm not the only one, I thought I was going mad.
[Nexus 5 Original Android Development] freshlysqueezed:
Were you undervolting with FKU with set on boot enabled and did you fail to reset/clear the FKU settings between flashing r55 to r56?
[Nexus 5 Original Android Development] ColdFire InOx:
Yes, I did. I always use the "flash automatically" option, so thinking of reseting settings to stock didn't even come to mind. That must have been the issue though.
[Nexus 5 Original Android Development] mendozaram:
That happen to me with my N4 and was a damaged charger
[Nexus 5 Original Android Development] freshlysqueezed:
Public service announcement:

If you undervolt, please reset/clear FKU settings before flashing a newer kernel version.
[Nexus 5 Original Android Development] Red5:
Thats all it took to get you out of here? Im surprised. Franco should have removed it months ago.

Pfft, leaving because you cant undervolt by -50. That extra 4 minutes of screen on time is a real deal breaker for some people.

At least 1/3 of the 'issues' being reported all comes form undervolting. I dont blame Franco one bit.
[Nexus 5 Original Android Development] freshlysqueezed:
Or at least not knowing to reset/clear FKU between flashing the newer kernel.
[Nexus 5 Original Android Development] LiquidSolstice:
Feel free to bug another developer about your useless undervolting. :) Bye!
[Nexus 5 Original Android Development] Clauu:
What is the default value for hotplug-load_threshold? I see a value of 80, i even reset & uninstall fku / reflash kernel and still same value
[Nexus 5 Original Android Development] Laggalot:
please don't remove the undervolting just because of some stupid trolls that are reporting placebos! i love this kernel because it offers so much tweakabilitys and if UV. gets deactivated I might have to wait until a guy takes your kernel and brings in UV back in the standard android development section which definitely would happen as it already does with linaro versions (which I dont really have any knowledge about)

Gesendet von meinem Nexus 5 mit Tapatalk
[Nexus 5 Original Android Development] rowdyw:
It was 70, but it looks like Franco changed it to 80 recently (r56?).
[Nexus 5 Original Android Development] menting:
Saying undervolting is useless is like saying a resolution of more than 720p on a 5-in screen is useless.

Heck, even the chip designers agree undervolting is useful up to a certain point. Why else would the cpu voltage change with changing frequency? If it is useless, they'd be running the same Vdd at all CPU frequencies
[Nexus 5 Original Android Development] LiquidSolstice:
....no, those two statements are not remotely similar in any way.
[Nexus 5 Original Android Development] Clauu:
I also changed to 80 in the past as for me at least it;s a good value and i was thinking that mysteriously it remains the same old value :p
[Nexus 5 Original Android Development] menting:
really? how so?

just because you think one is useless and the other not doesn't make it automatically true.
[Nexus 5 Original Android Development] JNewms:
Because UV really doesn't do anything. It may lower your CPU temp slightly, but it doesn't prolong battery life.

---------- Post added at 06:22 PM ---------- Previous post was at 06:20 PM ----------

---------- Post added at 06:22 PM ---------- Previous post was at 06:22 PM ----------

56 hasn't broken anything. If your device was messed up, then chalk it up to user error. I've been flashing 56 across different ROMs, trying to replicate all of these "broke my device" conditions, and have not been able to find one problem.

---------- Post added at 06:24 PM ---------- Previous post was at 06:23 PM ----------

56 hasn't broken anything. If your device was messed up, then chalk it up to user error. I've been flashing 56 across different ROMs, trying to replicate all of these "broke my device" conditions, and have not been able to find one problem.
[Nexus 5 Original Android Development] menting:
Here's a quick research paper that says otherwise

"Dynamic voltage and frequency scaling (DVFS) is a well-known technique to reduce energy in digital systems...."

energy reduction = prolong battery life. I'm pretty sure nobody can argue against that.

http://www.eecs.harvard.edu/~meeta/my_papers/hpca08_onchipvrm.pdf

FWIW, even a 0.1% is something. The argument should not be whether it is useless or not, because clearly it's not useless. The argument should be whether the gains are enough to spend the time/trouble on it. But that decision should be made by the end user.

Example: I don't believe spending more than 10 sec working on my car is worth my time for any performance gain, but it might be worth it for someone.
[Nexus 5 Original Android Development] JNewms:
56 hasn't broken anything. If your device was messed up, then chalk it up to user error. I've been flashing 56 across different ROMs, trying to replicate all of these "broke my device" conditions, and have not been able to find one problem.
[Nexus 5 Original Android Development] LiquidSolstice:
There you go, a certain point. When you undervolt a top end frequency, you introduce instability when the device needs its power the most. When you undervolt a low end frequency, you introduce instability when the device is sleeping and engaging in background processes. The exact reason why chip designers don't expose voltage controls to users by default is because users who don't understand how their SoC (or electriciity, for that matter) works will either fry their chip or cause serious instability, and will blame the OEM.

That's exactly what's happening here; people are undervolting, they're getting reboots due to instability, and franco has had it up to here with that nonsense. It is useless because the actual battery gains you get by a simple -50 uv is absolutely trivial when the tradeoff is instability.

You are not a skilled kernel developer. Franco is. If he believed that all his users would benefit from UV, he would leave it in. Because of people who don't know what they're doing, he has extra unnecessarily and irritating variables to deal with. All of that on top of the fact that it's been proven many, many times over again that their is not statistically significant battery gain to be had by undervolting, and that makes all of this useless. Unless you can prove otherwise, it's not worth the hassle for anyone.
[Nexus 5 Original Android Development] menting:
you're going off your argument.

I agree with you that people b*tch and moan when they undervolt and start crashing, but your original argument said undervolting is useless, which is clearly wrong.

I'm not a skilled kernel developer that's for sure. Heck, I'm not even a kernel developer at all. But I've been working in the semiconductor industry for about 11 yrs (DRAM mostly, and processors for ~2yrs), and it really pisses me off when people say undervolt is useless, when it clearly is, with the caveat that it only works well up to a certain point.

People that undervolt should be told that they risk the stability of the chip if they do so, and if they can handle that risk, then go ahead and do it. But they should not be told stuff that's simply untrue.

Edit: "you introduce instability when the device is sleeping and engaging in background processes" => this statement is only true when the voltage is operating at boundary conditions. It could occur at low or high voltage, depending on what the device is doing. It is not a guaranteed instability when voltage is dropped.