Database Users

Kernel troubles

I just installed a new kernel, and it caused a boot loop. How can I go back to my old stock kernel without using the RUU, because if use that, i'll lose my root :/

Did you clear your cache and dalvik cache before installing ?

No, was i supposed to? :/ sorry if i missed directions, i was pretty careless about this.

dhMassacre said:
No, was i supposed to? :/ sorry if i missed directions, i was pretty careless about this.
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Click to collapse
Yes. Always or you will get FC's and have to Factory Wipe and lose your data. If you have a nand backup, restore it prior to the kernal. ALWAYS backup before installing a kernal. Also they say use Amon RA Recovery. I guess ClockworkMod does not wipe the Dalvik Cache and Cache properly.
Make sure you read stuff over and over when it involves rooting, flashing a radio and kernel. I used the ClockworkMod to wipe the cache and dalvik cache and installed the Kernel and it disabled my usb and sdcard. That is not fun trying to get back working. Make sure you do that.

For those with CM 6.1 battery drain...

A quick backup, wipe, reflash, restore apps worked for me...just saying.
battery is at 50% now, after 12 hours of moderate use. Whereas before it would be beyond dead.
Wonder what could have caused this? I've flashed RC2-4 with the same battery drain problem (no wipe). Any insight?

Just have to make sure you wipe cache and dalvik before upgrading to new cm. Its the proper way to upgrade as far as the kernel goes. That should be your steps as far as flashing any kernels. Battery life on stable version seems a lot better to me. I can go well over 24 hours of use with good usuage.
[G2/HTC Vision]

luis86dr said:
Just have to make sure you wipe cache and dalvik before upgrading to new cm. Its the proper way to upgrade as far as the kernel goes. That should be your steps as far as flashing any kernels. Battery life on stable version seems a lot better to me. I can go well over 24 hours of use with good usuage.
[G2/HTC Vision]
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Click to collapse
u using cm kernel or pershoot?

luis86dr said:
Just have to make sure you wipe cache and dalvik before upgrading to new cm. Its the proper way to upgrade as far as the kernel goes. That should be your steps as far as flashing any kernels. Battery life on stable version seems a lot better to me. I can go well over 24 hours of use with good usuage.
[G2/HTC Vision]
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Click to collapse
ah, yes. :facepalm: forgot to include that
wipe dalvik, cache, and battery stats.

I'm using cyanogens kernel. With all my profiles set to the ondemand governor. You'll see a big difference in battery life. Pershoots kernel is amazing as well. I've used both. I get great battery life with either.
[G2/HTC Vision]

bdong said:
A quick backup, wipe, reflash, restore apps worked for me...just saying.
battery is at 50% now, after 12 hours of moderate use. Whereas before it would be beyond dead.
Wonder what could have caused this? I've flashed RC2-4 with the same battery drain problem (no wipe). Any insight?
Click to expand...
Click to collapse
Backup from Within Rom Manager or in the Recovery?

There's 1 thing that confuses me. In recovery, it has the Wipe data/factory reset, wipe cache partition and in the advanced menu, it has the wipe davlik cache. Do i wipe the data AND cache partition with the davlik cache? Just keep seeing people mention 2 wipes, but there's option of 3 from recovery to choose from.

ok11 said:
There's 1 thing that confuses me. In recovery, it has the Wipe data/factory reset, wipe cache partition and in the advanced menu, it has the wipe davlik cache. Do i wipe the data AND cache partition with the davlik cache? Just keep seeing people mention 2 wipes, but there's option of 3 from recovery to choose from.
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Click to collapse
If your upgrading to a new version of CM OR flashing a new kernel you ONLY wipe cache (NOT DATA/CACHE aka Factory Wipe) and you wipe Dalvik cache under advanced menu.

luis86dr said:
If your upgrading to a new version of CM OR flashing a new kernel you ONLY wipe cache (NOT DATA/CACHE aka Factory Wipe) and you wipe Dalvik cache under advanced menu.
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Click to collapse
Thanks for clarifying that for me.

Need info about cyanogen mod installation

Hey guys
I had started to use nightly builds. My question is should I have to wipe factory n Cache?
Sent from my Nexus S using XDA Premium App

Nope, if you continue to use the nightlies, just wipe dalvik cache,
If you come from different rom, just wipe data and cache and dalvik cache.

Once you are on the nightlies you never wipe anything. Don't listen to any nonsense about caches and dalviks just go to recovery, flash nightly, reboot!
Sent from my Nexus S using XDA App

Thank you.. do I have to wipe if I'm switching to different rom of same version?
Sent from my Nexus S using XDA Premium App

You're losing no data wiping cache and dalvik, why not do it then, it saves you from trouble.

rentaric said:
You're losing no data wiping cache and dalvik, why not do it then, it saves you from trouble.
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Click to collapse
Because it doesn't "save you from trouble." But I'm not going to argue about it. The OP asked if he had to wipe when upgrading nightlies and the answer is No.
Sent from my Nexus S using XDA App

Plz tel about this... Toll then do I have to wipe if I'm flashing different rom of same android version!?
Sent from my Nexus S using XDA Premium App

ancilary said:
Plz tel about this... Toll then do I have to wipe if I'm flashing different rom of same android version!?
Sent from my Nexus S using XDA Premium App
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Click to collapse
Yes for different roms you must factory reset.
Sent from my Nexus S using XDA App

rentaric said:
You're losing no data wiping cache and dalvik, why not do it then, it saves you from trouble.
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Click to collapse
Correct.
matt2053 said:
Because it doesn't "save you from trouble." But I'm not going to argue about it. The OP asked if he had to wipe when upgrading nightlies and the answer is No.
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Click to collapse
You are so wrong. Of course he needs to wipe Dalvik and Cache even if he installs another nightly. Its because the new nighlties bring new apps versions, or new kernel changes. Deleting Dalvik and cache forces the Android to reload the Dalvik cache for all the apps. Also, it saves you from trouble of incompatibility or FC's.
ancilary said:
Plz tel about this... Toll then do I have to wipe if I'm flashing different rom of same android version!?
Sent from my Nexus S using XDA Premium App
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Click to collapse
Different ROM same Android - wipe Data, Dalvik, Cache.
Same ROM same Android - wipe Dalvik, Cache.

brainmaster said:
Correct.
You are so wrong. Of course he needs to wipe Dalvik and Cache even if he installs another nightly. Its because the new nighlties bring new apps versions, or new kernel changes. Deleting Dalvik and cache forces the Android to reload the Dalvik cache for all the apps. Also, it saves you from trouble of incompatibility or FC's.
Different ROM same Android - wipe Data, Dalvik, Cache.
Same ROM same Android - wipe Dalvik, Cache.
Click to expand...
Click to collapse
Well you can have your superstitions but there is no rational reason to manually wipe your cache or your dalvik cache when upgrading CM nightlies, and that comes straight from the developers of the ROM who are more knowledgeable than I am. None of the CM devs have EVER suggested it, and when asked, have said that it is not something that should be done. I will take their word over yours.
EDIT: This is the closest I think we will find to a definitive answer: http://review.cyanogenmod.com/#change,4933
So, CM development team does not suggest a wipe of dalvik or cache when upgrading. The nightly installation instructions do not mention wiping dalvik or cache. I personally have flashed several hundred nightlies over the last year and have never wiped cache or dalvik when upgrading. Many many other users have flashed hundreds of nightlies each and have not wiped cache or dalvik and have not had problems. There is no reason to do this action, it is completely pointless. It is like saying "you must have your phone pointing to the east when you boot." Sure maybe it does not hurt anything but we don't really need to keep spreading this superstition.
EDIT: In re-reading this I feel like my posts come across as disrespectful and/or antagonistic. I simply disagree with what was said and I feel I have good reason to. But the OP can read about both points of view and then try for himself and choose what works best for him.

CWM recovery was developed from CM7 devs. So why do you think that they've integrated or made a option to wipe dalvik if that is not needed?
Especially if installing another kernel, wiping Dalvik is a must.
But you are right, the OP can choose himself either he will do that or not.
I don't think that your post is disrespectful and/or antagonistic, you have just expressed your opinion. If we don't discus issues with each other we are not gonna make any progress on learning.

brainmaster said:
CWM recovery was developed from CM7 devs. So why do you think that they've integrated or made a option to wipe dalvik if that is not needed?
Click to expand...
Click to collapse
There are lots of options in CWM recovery that are not needed when flashing
Like I said, in the link it is expressed very clearly that the developers of the ROM feel it is "completely pointless" (exact words) to wipe cache and dalvik when updating to newer CM build.
There are times when a user or developer might want to wipe cache or dalvik and so those options do exist. There are other partitions that a user or developer might want to format from time to time for various reasons as well. And the option to do those things is there in CWM recovery. But that does not mean they should be done every time, just because they are there.
In the link I posted, a submission was made to CM code to make it easier for users to wipe dalvik and cache and install a zip all in one command. The submission was rejected because the reviewers agreed that it was "completely pointless."
Why after so much time do you think "Wipe Dalvik Cache" is still obscurely placed in the "Advanced" menu of CWM Recovery? It would be very easy and simple to wipe cache and dalvik automatically when installing a ROM through CWM Recovery or at least put the option on the main page. Do you think that Koush just likes to give users a hard time? Do you think he wants it to be difficult for them to update their ROMs? I don't think so. I think he understand that it is an advanced function that can be useful in some circumstances but is not typically needed in 99% of cases.

The developers also note that the cache is invalidated via hashes automatically. So its basically auto wiped.
The only reason that I wipe is when the nightly contains a new kernel, dalvik should be wiped to eliminate possible problems.
Sent from my Nexus S 4G using Tapatalk

*Kernel flashing question *

When flashing to a new kernel, do I need to write my device or can I just flash from where I am? Currently I'm on matr1x kernel and I want to go to Franko's kernel. I was planning on wiping the dalvik cache but not factory reset. I'd rather not lose all my apps and settings if I can help it. Any ideas?
Sent from my Nexus 4 using xda premium

Just wipe cache and dalvik and your set to go!
Sent from Nexus 4

itpromike said:
When flashing to a new kernel, do I need to write my device or can I just flash from where I am? Currently I'm on matr1x kernel and I want to go to Franko's kernel. I was planning on wiping the dalvik cache but not factory reset. I'd rather not lose all my apps and settings if I can help it. Any ideas?
Sent from my Nexus 4 using xda premium
Click to expand...
Click to collapse
You don't need to factory reset when flashing kernels just wipe cache and dalvik and you'll be fine. Note it might take a little longer to boot because it will be building up cache since you just wiped it.

No need to wipe anything. No cache or dalvik needed either. You just flash and boot!
BUT! When you are using a custom kernel that uses custom ramdisk (ex. Franco), you need to flash the kernel from your ROM first. (I usually just backup only my boot image in TWRP so I can go back and forth between kernels) If you don't, the phone might not boot (will boot to bootloader, which in that case, you can fix the problem)
Also, make sure that you don't overclock too much and expect bugs from nightly releases (a lot of kernels are in nightly version right now, but Franco seems to reach milestone soon). You might not experience any bugs, but you never know.

you should be able to do that
if it is just a zip, you should be able to flash it right across in the recovery.
I just did that an hour ago, it kept everything except the kernel.
itpromike said:
When flashing to a new kernel, do I need to write my device or can I just flash from where I am? Currently I'm on matr1x kernel and I want to go to Franko's kernel. I was planning on wiping the dalvik cache but not factory reset. I'd rather not lose all my apps and settings if I can help it. Any ideas?
Sent from my Nexus 4 using xda premium
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Click to collapse

[Q] Nexus 4 Kernel, ROM and nandroid

I have a Nexus 4.
To flash a kernel all I need to do is to go to recovery mode,
Install zip from sd card,
Choose zip from SD card,
Pick the kernel's zip file,
Press yes and reboot the system?
Don't I need to wipe anything like when flashing a new rom?
And should I flash the kernel and then the ROM and GApps,
Or flash the ROM and GApps and then flash the kernel?
If my device acts weird after I flashed the kernel,
And I did a nandroid backup before that (I backed up with a ROM and stock kernel),
After I restore it, will everything be like what it was before I flashed the kernel (Will I have to flash the ROM again?)
Thank you in advance guys!

Yes thats how you install a kernel. Some people say to wipe cache and dalvik after installing, but its up to you.
Flash rom, gapps, then kernel.
When you restore the nandroid it will restore everything, including the rom and kernel that were installed at the time of taking the backup.
So yes...if stuff starts acting up, and you restore your nandroid that you took while on stock rom/kernel it should fix the issues. You dont have to flash the rom again...its included in the nandroid.

chromium96 said:
Yes thats how you install a kernel. Some people say to wipe cache and dalvik after installing, but its up to you.
Flash rom, gapps, then kernel.
When you restore the nandroid it will restore everything, including the rom and kernel that were installed at the time of taking the backup.
So yes...if stuff starts acting up, and you restore your nandroid that you took while on stock rom/kernel it should fix the issues. You dont have to flash the rom again...its included in the nandroid.
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Click to collapse
What will be different if I'll wipe cache and dalvik or not?

VIPOA said:
What will be different if I'll wipe cache and dalvik or not?
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Click to collapse
Not 100% sure, but f you wipe them your dalvik will be rebuilt on the next boot, and your cache will also be rebuilt once the system actually boots.
Theres no harm in wiping them.

VIPOA said:
What will be different if I'll wipe cache and dalvik or not?
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Click to collapse
you never have to wipe anything when flashing a kernel, nothing, regardless of what others say. the dalvik nor the cache have anything to do with kernels. its like taking a shower and washing your socks to put gas into your car.

chromium96 said:
Not 100% sure, but f you wipe them your dalvik will be rebuilt on the next boot, and your cache will also be rebuilt once the system actually boots.
Theres no harm in wiping them.
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Click to collapse
So my device will be OK if I'll wipe dalvik and cache before I flash a kernel, right?
simms22 said:
you never have to wipe anything when flashing a kernel, nothing, regardless of what others say. the dalvik nor the cache have anything to do with kernels. its like taking a shower and washing your socks to put gas into your car.
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Click to collapse
When you flash a kernel, do you wipe anything?

VIPOA said:
So my device will be OK if I'll wipe dalvik and cache before I flash a kernel, right?
When you flash a kernel, do you wipe anything?
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Click to collapse
your device will be ok wiping dalvik and cache, but there is no need to do it. there is never any need to wipe anything when flashing a kernel.

simms22 said:
your device will be ok wiping dalvik and cache, but there is no need to do it. there is never any need to wipe anything when flashing a kernel.
Click to expand...
Click to collapse
Do you wipe anything when you flash a kernel?
And does your kernel works OK without wiping?

VIPOA said:
Do you wipe anything when you flash a kernel?
And does your kernel works OK without wiping?
Click to expand...
Click to collapse
no, i dont. and it works great.

simms22 said:
no, i dont. and it works great.
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Click to collapse
OK. Thank you very much for the help
One last question, which kernel should I flash with PA?
FRANCO or TRINITY?

VIPOA said:
OK. Thank you very much for the help
One last question, which kernel should I flash with PA?
FRANCO or TRINITY?
Click to expand...
Click to collapse
try both, they are both good kernels. i use trinity, but francisco makes a good kernel too.

simms22 said:
try both, they are both good kernels. i use trinity, but francisco makes a good kernel too.
Click to expand...
Click to collapse
And two last questions,
How do I update a ROM?
Should I delete the zip files of previous Roms and kernels and keep only what I'm using (let's say PA 3.60 and Trinity/Franco kernels)?

VIPOA said:
And two last questions,
How do I update a ROM?
Should I delete the zip files of previous Roms and kernels and keep only what I'm using (let's say PA 3.60 and Trinity/Franco kernels)?
Click to expand...
Click to collapse
if you want, keep the current rom/kernel and the previous. thats probably the smartest way, in case one is buggy. but, at least, keep a copy of the current rom/kernel in your storage at all times, itll save you headaches later.
when you update a rom, flash it in your custom recovery. flash the rom, gapps if needed, and the kernel, the reboot. if youre just updating, you dont have to wipe anything. but if you are flashing a new rom, you do have to wipe data/factory reset.

simms22 said:
if you want, keep the current rom/kernel and the previous. thats probably the smartest way, in case one is buggy. but, at least, keep a copy of the current rom/kernel in your storage at all times, itll save you headaches later.
when you update a rom, flash it in your custom recovery. flash the rom, gapps if needed, and the kernel, the reboot. if youre just updating, you dont have to wipe anything. but if you are flashing a new rom, you do have to wipe data/factory reset.
Click to expand...
Click to collapse
OK
Thank you very much for the help
Will my ROM's settings be saved?

VIPOA said:
OK
Thank you very much for the help
Will my ROM's settings be saved?
Click to expand...
Click to collapse
if you are just updating, yes.

simms22 said:
if you are just updating, yes.
Click to expand...
Click to collapse
Can I use this and will it be OK (no bugs)?
http://forum.xda-developers.com/showthread.php?t=2227226

VIPOA said:
Can I use this and will it be OK (no bugs)?
http://forum.xda-developers.com/showthread.php?t=2227226
Click to expand...
Click to collapse
Always use your recovery to flash stuff its the safest way.
Sent from my Nexus 4

spaceman860 said:
Always use your recovery to flash stuff its the safest way.
Sent from my Nexus 4
Click to expand...
Click to collapse
OK
Thank you very much guys!