yashsingh1/xdaforums huggingface dataset:
[Galaxy S 4 Q&A, Help & Troubleshooting] DiDA™:
Hello everyone,

I just got my Galaxy S4 a couple of hours ago and i'm loving it! I've been an iPhone user for some time but I have had some experience on Androids before back when I had my Galaxy S3.

I'm familiar with Rooting and flashing custom ROMS but i'd like to try those built-in features the Galaxy S4 has before flashing Custom ROMS.

When I had my GS3, my favorite kernel was the "Siyah Kernel" because it had the Dual-Boot option. Is there something similar on the GS4?

Anyways, it's good to be back and i'll do my best to help out whenever I can.

Oh, and sorry if this is the wrong section but I couldn't find a proper one to post this.
[Android Q&A, Help & Troubleshooting] Maximum-King:
Hello???
[G2 Q&A, Help & Troubleshooting] popkurn611:
I just did a nandroid backup via CWM and when I go into my file manager my cwm folder is empty. If I go into recovery and act like I am going to restore a backup the file does show up in recovery but I am not seeing the file in my file manager when the phone is booted up. Any help is greatly appreciated.
[Galaxy Grand Duos i9082 Android Development] xenon92:
nebula kernel is for AOSP based KitKat android 4.4+ ROMs

and AOSP based Lollipop android 5.0+ ROMs

Download the latest PERFORMANCE CONTROL APP to utilize the full potential of the kernel.

Brief explanation of few of the features in nebula can be found in the third post. For more info, use Google.​

​

FEATURES

Compiled using the latest Linaro 4.9.1 - 2014-05 toolchain

Based on kernel version 3.0.101

Additional Governors: SmartassV2, SmartassH3, Lulzactive, LulzactiveQ

Additonal I/O Schedulers: ROW, SIO, SIOPLUS, VR, ZEN, BFQ

Overclock: 1.3 Ghz, 1.4 Ghz, 1.5 Ghz, 1.6 Ghz

F2FS support

CPU Boost driver

UKSM (Ultra KSM) support (enable it in Performance Control app)

Frandom

Dynamic Sync Control (enable it in Performance Control app)

Asynchronous FSync ported from HTC One

Cross Memory Attach

Entropy tweaks

Increased read-ahead from 16/128 to 32/2048 (can be customized in Performance Control app)

Disabled Cyclic Redundancy Checks (CRC) for better performance

Many patches, fixes and improvements from codeaurora

Many more performance and battery friendly tweaks

INSTALLATION

Download the latest nebula zip

Flash using CWM recovery

Wipe cache

Wipe dalvik cache

Reboot

NOTE

You are free to use kernel as the default kernel in your ROMs

Please DO NOT change the kernel name that shows up in Settings > About phone

Please link the nebula kernel thread in your ROM thread

DOWNLOADS

nebula kernel

(Please don't make mirror links of the kernel)
​

SOURCE

Source code of the kernel can be found at my Gihub.

CREDITS

- pawitp - nebula is based on his kernel source for CM11

- to all the developers whose mods I have included in my kernel

- [MENTION=943196]k2wl[/MENTION] - for his extensive guide on kernel compilation. Big thanx to him.

- [MENTION=5456406]CoolDevelopment[/MENTION]

- Christopher83 for the Linaro toolchains

​

XDA:DevDB Information

nebula kernel, Kernel for the Samsung Galaxy Grand Duos i9082

Contributors

xenon92

Source Code: https://github.com/xenon92/android_kernel_nebula

Kernel Special Features: Compiled using Linaro Toolchain to get the best performance. Scroll up for features.

Version Information

Status: Stable

Current Stable Version: v3.20

Stable Release Date: 2014-11-22

Created 2014-04-24

Last Updated 2014-11-22
[Galaxy Grand Duos i9082 Android Development] xenon92:
BRIEF EXPLANATION ABOUT KERNEL FEATURES​

​

UKSM

UKSM is about de-duplication of data in system memory rather than being another de-duplicating file-system. This improves RAM usage.

Dynamic Sync Control

The dynamic sync control interface uses Android kernel's unique early suspend / late resume interface. While screen is on, file sync is disabled. When screen is off, a file sync is called to flush all outstanding writes and restore file sync operation as normal.

Frandom

Frandom is a Linux kernel random number generator, which is 10-50 times faster than what you get from Linux' built-in /dev/urandom. It uses very little (/dev/frandom) or none (/dev/erandom) of the kernel's entropy pool, so it is very useful for applications that require a handy source for lots of random data.

CPU Boost driver

When certain bursty and important events take place, it might take a while for the current cpufreq governor to notice the new load and react to it. That would result in poor user experience. To alleviate this, the cpu-boost driver boosts the frequency of a CPU for a short duration to maintain good user experience while the governor catches up.

FAQ​

​

On which ROM can I install nebula?

- nebula can be used on any AOSP kitkat 4.4+ based ROM. (Carbon, SlimKat, CM11)

What is the best and most stable configuration for nebula?

- Configuration depends from user to user. Still, the most stable configuration according to me and that I use is below. It might differ for you.

- Governor: SmartassV2

- Max. freq: 1.2 Ghz (OCing doesn't really have an increased and noticeable performance, rather it heats the processor and wastes battery for a marginal gain in performance as well as creates instability - random reboots etc. Google more about OC.) (Read the description on this commit.)

- I/O Scheduler - SIO

- Enable UKSM (from Performance Control app)

- Enable Dynamic FSync (from Performance Control app)

- I'll update this configuration as more tweaks are added to nebula

I get random reboots, what should I do?

- I am working on the kernel for myself and the kernel is quite stable for me. Still, if you face reboots see below:

- Make sure you followed the installation instruction written in Post #1.

- Make sure you "Fix permissions".

- OCing will always cause instability. Try reducing the max frequency to 1.2 Ghz

- It is quite possible that you don't know how to use a custom kernel. Not everything needs to be set at HIGHEST. Just because an "option" is there doesn't mean you have to select it. Try changing the configuration that meets your needs and satisfies you. If you set up the kernel properly, it would stop giving you random reboots.

- The only way to get things fixed is to provide logs. I cannot fix that I cannot see. Google, how to take logs to find and solve kernel issues. (kmsg/last_kmsg)

- Tell me a way in which I can reproduce the issue on my phone.
[Galaxy Grand Duos i9082 Android Development] CoolDevelopment:
Does hotplugging work well with zzmove governor? I remember trying hotplug on s2vep and it freezed almost everytime while deep-sleeping.
[Galaxy Grand Duos i9082 Android Development] xenon92:
Same issue on baffin too. That's why I have removed zzmoove from the kernel.
[Galaxy Grand Duos i9082 Android Development] Soureen:
hmm... xenon92... already k2wl has made a custom kernel with O.C till 1.8GHz so why have you the max @ 1.6GHz ?
[Galaxy Grand Duos i9082 Android Development] parag tetambe:
Its Oc upto 1.7 Ghz not 1.8

Sent from my GT-I9082
[Galaxy Grand Duos i9082 Android Development] mukeshpacheria:
and he is present new build with new modification

its make wide development of grand :laugh:
[Galaxy Grand Duos i9082 Android Development] xenon92:
Read the description in this commit - Link

There has already been a discussion on CM11 thread about how much does it really benefit by OCing at higher frequencies. Refer to that thread's discussion for more info.

In short - OCing at too high frequency heats up the CPU (obviously) and doesn't necessarily increase performance.

Even though I have added OC till 1.6 Ghz, but even I don't use that setting. 1.2 Ghz is fine for me.
[Galaxy Grand Duos i9082 Android Development] Alldroidrider:
Another kernel for AOSP rom.....:laugh::laugh::good::good::good::good:

Installed the kernel in carbon ROM and is working fine....:good::good:

ll update more on the battery stat later...

:D:D:D:D
[Galaxy Grand Duos i9082 Android Development] raghavsharmaxda:
any FC's anybody facing?....anything at all..during call or anything??..just asking..would have tested myself but my net is limited right now till tomorrow......so can't :(..will surely tomorrow onwards download evry single one (as m xenon work fan lets say :P )...but wont risk using mbs if it got any bugs...:(
[Galaxy Grand Duos i9082 Android Development] naufalhadyan:
It's actually 1797 MHz, so let's say it's only 3MHz shy from 1.8 GHz :)

This kernel looks promising, I will download, install, and use it for a few days :D
[Galaxy Grand Duos i9082 Android Development] Alldroidrider:
No fcs and no issues with call, data, and msgs....

Been in interactive with 1200 max for an hour now...

Dint tried overclock though...:fingers-crossed:
[Galaxy Grand Duos i9082 Android Development] Sulaimanshariff:
I need a lil battery life guys my service provider doesn't have 3g for now some TRAI issues and i stay away frm hme most of the time so using 2g and the screentime i get max is 3 hrs 30 mins wid evolution kernel processor=conservative,I/O=sio or sio plus and today i reverted back to cm's stock kernel and have flashed the latest build my biggest issue is when my battery drops down to 30% it starts draining drastically say like for 2 mins from 30 to 24% any help would be definitely appreciated have made calibrations until now again calibrating tonight and will test after that nebula for sure because only name i knew for best custom roms was and is XENON92!;):thumbup:
[Galaxy Grand Duos i9082 Android Development] mukeshpacheria:
i set the cpu at 1.5 but when i restart the phone it rest to 1.2 i also check on set on reboot and try on uncheck on reboot
[Galaxy Grand Duos i9082 Android Development] naufalhadyan:
If the system did a forced reboot to avoid further CPU instability, the options will revert back to default... correct me if I'm wrong.

pawitp also said in the CM11 thread, that the options dont instantly set on system boot. You may have to wait 1 minute and check back.
[Galaxy Grand Duos i9082 Android Development] mukeshpacheria:
thanx mate ,,,, i read it also but forget

thanx again
[Galaxy Grand Duos i9082 Android Development] raystriker:
[MENTION=5273865]xenon92[/MENTION]

Nice work. Just checked the CM11 thread. The latest update upgrades their generic kernel to 3.0.101 :o . Any plans of updating yours?:laugh::good:
[Galaxy Grand Duos i9082 Android Development] xenon92:
nebula is already 3.0.101.
[Galaxy Grand Duos i9082 Android Development] raystriker:
Oh. I haven't tried it yet. My bad. (You could write that in the first post?);)
[Galaxy Grand Duos i9082 Android Development] skpadhi79:
Attaching screen shots of battery discharge cycle with RR 5.1.0 ( ART )and nebula kernel 2.6 ( Smartassh3+sio & 312/1200)...yes the back up during standby is good and i was able to make some 4 hrs 15 min of voice calls during those 2 days..

but my real concern is still the same as that of stock kernel in RR 5.1.0..when the screen is on for around 2 hrs..how the android OS is showing 3 hrs 45 min..BTW wifi was on for around 10 min only...and the android OS usage is still like say from 3 min to 10 min. to 22 min...like that..sudden surge..

as far as i remember that was not the case in RR 5.0.6..may be i am wrong also..

On the whole..a great rom and a great kernel....my grand is flying.............:good::good::good:.great work [MENTION=5273865]xenon92[/MENTION]...:):)
[Galaxy Grand Duos i9082 Android Development] xenon92:
nebula kernel updated to v2.9.

- Updated ROW I/O scheduler with many updates and fixes from codeaurora

- Update DEADLINE I/O scheduler by hardcoding values

- Fixed a bug in CFQ I/O scheduler

- Other performance tweaks

-----

[MENTION=5561484]skpadhi79[/MENTION]

Amazing battery backup, I must say. :)

nebula rocks! Hehe.
[Galaxy Grand Duos i9082 Android Development] fakhruddin.razi:
Should I flash it for battery backup . how much screen on time I may get hare
[Galaxy Grand Duos i9082 Android Development] RIPPER:
Flash it:thumbup:
[Galaxy Grand Duos i9082 Android Development] ##W4TCH0UT##:
Man, you rock xenon92. Great update!!!! Will attach battery backup soon.
[Galaxy Grand Duos i9082 Android Development] fakhruddin.razi:
Okay update first with screen on time

---------- Post added at 11:19 PM ---------- Previous post was at 11:16 PM ----------

Will it work on carbon rom
[Galaxy Grand Duos i9082 Android Development] skpadhi79:
So now its screen time........on RR 5.1.0 with ART run time with nebula kernel 2.6 ...conservative/cfq and 312/1200....voice calls around 30 min. and surprisingly android OS usage is 23 min. only....:good::good::good:

what more can i ask for...:):)
[Galaxy Grand Duos i9082 Android Development] jayc137:
That's fukin' awesome [emoji33][emoji33]

I am tempted to compile this for stock (for personal use only)
[Galaxy Grand Duos i9082 Android Development] mukeshpacheria:
Performance Control application not added into your latest kernal 2.9

i flash it with latest CM11 build

all work is awesome Thanx man
[Galaxy Grand Duos i9082 Android Development] RIPPER:
U have to install separately. Link is in OP
[Galaxy Grand Duos i9082 Android Development] mukeshpacheria:
:good:

Thanx
[Galaxy Grand Duos i9082 Android Development] ##W4TCH0UT##:
My turn:

Amazing:D

Umm... Xenon92, why did you revert all updates and based it to v2.6??? 2.9 is working amazingly well. Everyone, xenon92 changed op to version 3.00. But in downloads I can't find it. :D. 3.00 looks amazing.
[Galaxy Grand Duos i9082 Android Development] xenon92:
nebula kernel updated to v3.00.

- Added CPU Boost driver

- Reverted updates and based to v2.6

- Other performance tweaks

------

I was doing some testing and found that recent updates were causing a lot of performance degradation. Phone was giving a good battery backup (which you all have experienced), but performance was degraded in v2.8 and v2.9, but was amazing in 2.6. So I reverted my base to v2.6.

v3.00 also supports F2FS.

------

I'll be using two digit version numbers from now on. It gives me better control over the versions and releases.
[Galaxy Grand Duos i9082 Android Development] SH1M4BD3:
Will this kernel works on S2vep??if not would you make this kernel versions for our devices?THANKS

HereupComeahaAing
[Galaxy Grand Duos i9082 Android Development] mukeshpacheria:
your latest version 3.00 not support art

it gives much more FCs
[Galaxy Grand Duos i9082 Android Development] xenon92:
Kernels have nothing to do with runtime.
[Galaxy Grand Duos i9082 Android Development] ##W4TCH0UT##:
No fc's bro. I'm on rr 5.1.1.
[Galaxy Grand Duos i9082 Android Development] sharath412:
Completed one day with v.3.0, smooth, no reboot, no fc, no lags and awesome battery backup...

smartass h3 312/800 -sio :thumbup:
[Galaxy Grand Duos i9082 Android Development] supersaayuj:
Don't know why...

But whenever i use any custom kernel my fav game Asphalt 8 (latest ver 1.3.2 i think) starts to lag...i mean EXTREME laginess

On normal use its just fine...i had to revert back to stock kernel of RR

My setting of kernel..On normal conditions

governor= smartassv2

scheduler=sio

UKSM = enabled

Fsync=enabled

My setting of kernel..when gaming

governor= interactive

scheduler=sio or row

UKSM = enabled

Fsync=enabled

Can anyone help me...:(
[Galaxy Grand Duos i9082 Android Development] fakhruddin.razi:
How do you get such backup ? I am also using RR 5.1.1 latest version with android run time and nebula kernel 2.6 .but I am getting only 4 min for 1%. Please help brother
[Galaxy Grand Duos i9082 Android Development] skpadhi79:
Nuthin special.. Just having dark still wallpapers n manual brightness set at around 15-20%... Try to charge ur battery from 30-35% to a full charge.. Me always sticking with stock charger n cable.. Hv also installed only essential apps for me

BTW that display test was only for experimental purpose with no on screen activity.. Only keeping the display on continuously to have a look on screen on time n corresponding battery discharge.. 1%@4 min goes to around 5 hrs upto 20% isnt bad either.. :good:
[Galaxy Grand Duos i9082 Android Development] xenon92:
nebula kernel updated to v3.02. 20140511

- CPU Boost driver - set tunables

- Wait just 1 second, instead of 4 seconds for other CPU core to halt

- Other performance tweaks
[Galaxy Grand Duos i9082 Android Development] Gibz97:
Deleted*
[Galaxy Grand Duos i9082 Android Development] androidbaba:
Cooldevelopement's cm11??:what:is it diff from [MENTION=3117667]pawitp[/MENTION]'s cm11? Can you give link??
[Galaxy Grand Duos i9082 Android Development] sty_erk94:
anyone knows how to backup current kernel?
[Galaxy Grand Duos i9082 Android Development] Darian71:
Any chance Nebula will make it to the S3 i747????? ???

I'm using it with the Grand I sold to my good friend with great results! ?
[Galaxy Grand Duos i9082 Android Development] Gibz97:
Sorry wrong thread. I meant to post here http://xdaforums.com/showthread.php?p=52555105
[Galaxy Grand Duos i9082 Android Development] neawasthi:
No need to backup, just reflash the kernel zip from recovery. I tried this in past with no issues (If you are already on custom kernel). Might need to clear the cache.

If you want to revert back to the kernel in ROM, you will need to reflash the ROM. NO NEED TO DO FACTORY RESET. Just flash and clear cache. kernel will be restored.
[Galaxy Grand Duos i9082 Android Development] neawasthi:
Great performance.. I already feel that games are running much smoother since I moved to this kernel. No heating / FCs.

Battery backup has become amazing ! On avg its ~30 hour with decent screen on (~4+hr) + ~1+hr on call.

Thanks for your effort on this !
[Galaxy Grand Duos i9082 Android Development] VanshKhanna:
Which rom are you using???
[Galaxy Grand Duos i9082 Android Development] neawasthi:
RR 5.1.1

Nebula 3.0.2 (ondemand / ROW)
[Galaxy Grand Duos i9082 Android Development] xenon92:
nebula kernel updated to v3.04.

- CPU Boost driver - decrease aggressiveness

- New governor - LulzactiveQ

- New I/O scheduler - SIOPLUS

- Other fixes and performance tweaks

-----

When I set tunables in v3.02 for cpu-boost driver, the driver became very aggressive and was using a lot of battery. I have toned down the parameters in v3.04 and battery backup is again as it was before v3.02.
[Galaxy Grand Duos i9082 Android Development] VanshKhanna:
Thanx a lot ! Again a great update, after updating the kernal the performance and battery backup has drastically improved

Plz tell a lil more about lulzactiveq and sioplus
[Galaxy Grand Duos i9082 Android Development] kiridhruv:
When i was on this kernel...

And i unlock mobile.. Every running process closes... I knw it improve ram.. But.. I dont want my floating launcher.. Antivirus to force close..

I have checked with other task killer everything is okay.

So plz tell me if i need to change any setting in this kernel..

Also... i was using performance control with this kernel tooo
[Galaxy Grand Duos i9082 Android Development] RIPPER:
Wooooooooohhhhh...not a single drop in battery%. This update is best in all.:thumbup::thumbup::thumbup:
[Galaxy Grand Duos i9082 Android Development] fakhruddin.razi:
Hey xenon I respect you . but please can you tell me which configuration is suitable for hard gaming ?
[Galaxy Grand Duos i9082 Android Development] sharath412:
Do u mind sharing your governor and ioscheduler settings?
[Galaxy Grand Duos i9082 Android Development] fakhruddin.razi:
+1
[Galaxy Grand Duos i9082 Android Development] RIPPER:
SmartH3 governor

Sioplus scheduler

Ksm enabled

Ultra ksm tweak

Vm settings tweak

Not a single drop by I mean kept fone for 3 hours with everything on without doin any thing
[Galaxy Grand Duos i9082 Android Development] skpadhi79:
+1...till now the best getting awesome performance with latest carbon rom.............:good::good: [MENTION=5273865]xenon92[/MENTION]...u have been really phenomenal.....:):)
[Galaxy Grand Duos i9082 Android Development] mukeshpacheria:
xenon your work is always awesome ,, we appreciate it

but i want to know that are you working on stock kernel ?
[Galaxy Grand Duos i9082 Android Development] jayc137:
Yep.

Atleast his github tells that.
[Galaxy Grand Duos i9082 Android Development] xenon92:
I prefer releasing a kernel after I've tested it myself. I did compile nebula kernel for stock based ROMs and it is booting too. But I do not have time these days to test it completely. I'll release it when I have time and have done a little bit of testing on it.
[Galaxy Grand Duos i9082 Android Development] mukeshpacheria:
THANX and good luck

if you don't mind then i will be the beta tester for stock kenel:fingers-crossed:
[Galaxy Grand Duos i9082 Android Development] xenon92:
nebula kernel updated to v3.10.

- Compiled using the latest Linaro 4.9.1 - 2014.04 toolchain (check screenshot attached)

- Memory management - lazy cache flushing on non-mapped pages

- Many updates to Device Mapper

- Use proper memory barriers for bitops

- softirq: reduce latencies

- sync: don't block the flusher thread waiting on IO

- ext4: Speed up FITRIM by recording flags in ext4_group_info

- ext4: speed up truncate/unlink by not using bforget() unless needed

- vmscan: add customisable shrinker batch size

- Other fixes and performance tweaks

-----

Skipped a few version numbers as this is a major release. Linaro 4.9.1 !!!

Antutu benchmarks are much better now (they don't show the complete picture though). So if I was to trust them, then there is definitely big performance improvement! :) Time will tell more.
[Galaxy Grand Duos i9082 Android Development] fakhruddin.razi:
Will it be battery friendly
[Galaxy Grand Duos i9082 Android Development] RIPPER:
Certainly Gooooood [MENTION=5273865]xenon92[/MENTION]:D:D:D:D:D:D
[Galaxy Grand Duos i9082 Android Development] fakhruddin.razi:
Good what about the battery
[Galaxy Grand Duos i9082 Android Development] RIPPER:
Benchmark!!..how can you test battery just 5 min after flashing:silly::silly::silly::silly:
[Galaxy Grand Duos i9082 Android Development] grsaridhtc:
sio plus

LulzactiveQ

Cosmic v4.1 + ART + F2FS
[Galaxy Grand Duos i9082 Android Development] maxxinn:
What is your ultra ksm tweaks bro??:confused::confused:
[Galaxy Grand Duos i9082 Android Development] VanshKhanna:
What about battery backup after the latest update
[Galaxy Grand Duos i9082 Android Development] Darian71:
[MENTION=5273865]xenon92[/MENTION], you may already be aware, but if not, this has folks talking. http://xdaforums.com/showthread.php?t=2754997
[Galaxy Grand Duos i9082 Android Development] xenon92:
I have heard that 4.8 requires many patches, not just one or two. That was some time ago, so things might have changed now. Therefore I never tried 4.8, too much of work is no go for me. I am lazy. :p

But next time I compile a ROM, I'll try 4.8 with archi's flags. Thank you for the link.
[Galaxy Grand Duos i9082 Android Development] sty_erk94:
I have problem when I want to charge the battery with the state of the mobile phone being turned off, a few minutes later the device restarts and the phone turn on again. :confused:

So, I can no longer charge the battery in a state of the device is turned off.:(

I faced this issue after flashing this kernel.

My Grand is using RR rom v.5.1.1 for now..

Please anyone know what the cause and how to solve it? Thank's. :D:good:
[Galaxy Grand Duos i9082 Android Development] fakhruddin.razi:
Please can anyone help me by providing which configuration is best for hard/hd gaming
[Galaxy Grand Duos i9082 Android Development] neawasthi:
battery backup is same as v3.02 (which was amazing..) . Still can see phone lasting for around 27-30hrs easily with decent phone use (4-5 hrs screen on, ~1 hr call)

---------- Post added at 06:12 AM ---------- Previous post was at 06:09 AM ----------

battery backup is same as v3.02 (which was amazing..) . Still can see phone lasting for around 27-30hrs easily with decent phone use (4-5 hrs screen on, ~1 hr call)

Try Governor-Performance | IO- ROW | KSM Enabled.

I tried few games and all look smoother than before.
[Galaxy Grand Duos i9082 Android Development] skpadhi79:
yes...same here...with latest carbon rom and nebula 3.10..device is restarting from power off position just after 1-2 min of putting in charge...:good::good: