Hello all
How often should you clear cache or fix permission using CWM?
Jim
Sent from my VEGAn-TAB using XDA
Personally I do it when ever the ROM that I am on starts acting a bit quirky. Which is not very often if you are running a stable build like VeganTab, CM7 or even the Froyo ROMs that have been out for a while. If you ever see yourself loading up a bunch of apps and running them allot. Over time you might would want to clear the cache and definitely fix permissions to get things back in order.
jweir said:
How often should you clear cache or fix permission using CWM?
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Click to collapse
They're not something you need to do often, or even occasionally, as part of some preventive maintenance regimen.
If you switch ROMs, then you will have to clear cache. Actually, it's best to do a "wipe data/factory reset" in CWM in this case--cache will get formatted in the process.
You would want to clear cache if you upgrade the current ROM; it is better, though, to instead wipe dalvik-cache. Similarly, if you upgrade an app manually--ie. not via the Market or the usual Android update process: eg. by overwriting an app in /system/app or /data/app and rebooting the system--you might want to clear cache.
You might have to clear cache after powering on the tablet after a long (weeks, months) period of inactivity. In this case, the battery will go flat and the system will lose its date and time--going back in time, so to speak. This might, in turn,cause cached data to go out of whack--though Android should take care of this normally.
The "fix permissions" step is needed even less. This link explains why you would want to use it: Again, it might be needed after a ROM update, and not otherwise. This means that doing a fix permissions after a SD card repartition or a wipe data/factory reset step is nonsensical--the fix_permissions script operates on existing data.
hi,
this ROM works very nice for me, thanks all the deveopers!
i have few questions:
(1) since this ROM has OTA updater (it seems, from the changelog), next time when the new version is realeased, can i just update the ROM via OTA updater?
(2) i dont really understand what “Wipe cache/dalvik” and “Wipe data / factory reset” really do. my guess is that “Wipe data / factory reset” repartitions the internal flash memory of the original memory, so we can use all the memory for our purpose. (not like original Nook Tablet, in which they dedicate only 1GB for personal usage)
if i understand all these correctly, this means next time if i flash the new ROM and want to keep the old data, i should not do "Wipe data / factory reset", but only need to do "Wipe cache/dalvik"? is this correct?
thanks so much,
Jun
junkoi said:
hi,
this ROM works very nice for me, thanks all the deveopers!
i have few questions:
(1) since this ROM has OTA updater (it seems, from the changelog), next time when the new version is realeased, can i just update the ROM via OTA updater?
(2) i dont really understand what “Wipe cache/dalvik” and “Wipe data / factory reset” really do. my guess is that “Wipe data / factory reset” repartitions the internal flash memory of the original memory, so we can use all the memory for our purpose. (not like original Nook Tablet, in which they dedicate only 1GB for personal usage)
if i understand all these correctly, this means next time if i flash the new ROM and want to keep the old data, i should not do "Wipe data / factory reset", but only need to do "Wipe cache/dalvik"? is this correct?
thanks so much,
Jun
Click to expand...
Click to collapse
Wipe data/factory reset is an option in CWM Recovery. Really all it does (from the screen messages) is format both /data and /cache.
Assuming you have CWM Recovery (though I imagine that there are similar entries in TWRP, I've just never used it), to wipe both of the caches you will first need to go to the entry "Wipe Cache Partition", which I believe is directly below Wipe Data/Factory Reset. Do that 3x (that's always been the recommendation, anyway) then go to Advanced and click on Wipe Dalvik Cache (again, 3x).
Again, assuming CWM Recovery, when you're in the recovery Vol Up/Down goes up and down in the list, the 'n' key is for Enter, and the Pwr button goes back.
I don't know about the OTA Updater. I always download and install ROMs (on both my phone and my NT) via Recovery.
Since this is a CM10 based rom you probably don't want to do the ota updater since that is a Cyanogenmod feature. This rom is optimized for the Nook from the CM10 Source I would presume. I personally tried the ota uldater since i get the notifications all the time but i get an error message something like "can't verify the source with a string of numbers". Stick to the recovery based flash installation.
Sent from my SPH-L710 using xda app-developers app
---------- Post added at 10:48 AM ---------- Previous post was at 10:10 AM ----------
I agree with liquidzoo that you should probably do the wipe cache, wipe dalvik cache and factory reset 3times seems like overkill but you can never be too safe. Also i use twrp recovery and click the system button and wipe system a few times as well.
Sent from my SPH-L710 using xda app-developers app
kobhomye said:
I agree with liquidzoo that you should probably do the wipe cache, wipe dalvik cache and factory reset 3times seems like overkill but you can never be too safe. Also i use twrp recovery and click the system button and wipe system a few times as well.
Sent from my SPH-L710 using xda app-developers app
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Click to collapse
I wipe /system 3x as well (under Mounts in CWM Recovery) when I'm installing a new ROM.
liquidzoo said:
I wipe /system 3x as well (under Mounts in CWM Recovery) when I'm installing a new ROM.
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Click to collapse
I'm not picking on you personally, but deleting and/or wiping partitions (in the case of /system) or directories (dalvik-cache) three times as opposed to once is completely unnecessary. You'll gain nothing by running the command three times over running it once, assuming you received no errors the first time.
When wiping the dalvik cache, both CM recovery and TWRP perform an "rm -rf /data/dalvik-cache" command using the shell. It's not Windows, and is unlikely to fail when passed the "-f (force)" option along with the "-r (recursive)" option.
In the case of wiping the /system partition, again both CM and TWRP write out zeros to clear the data on the partition. I would be suprised if CWM acted differently from CM and TWRP when wiping dalvik-cache and /system.
The only reason I bothered to look into what these commands actually do is to prevent a user from thinking there's a corellation between a failure to wipe 3x versus a problem they're having. If a 3x wipe "fixes" something for you, whatever the problem was, it's very unlikely that the second or third wipe was what fixed it but instead it was more likely a result of a clean install of the ROM.
References from source:
TWRP Wipe Dalvik - https://github.com/TeamWin/Team-Win...548de276b62c0e9af8661e/extra-functions.c#L986
TWRP Wipe/Format System - https://github.com/TeamWin/Team-Win...8de276b62c0e9af8661e/mtdutils/mtdutils.c#L498
CM Wipe Dalvik - https://github.com/CyanogenMod/andr...aa7ff3d06d5dd115b16c/extendedcommands.c#L1292
CM Wipe/Format System - https://github.com/CyanogenMod/andr...aa7ff3d06d5dd115b16c/mtdutils/mtdutils.c#L498
Have fun modding!
No worries, it's just something I've always done as it's been recommended to me in the past (there are some ROM developers that recommend 5x, actually). I'm not saying that 3x over 1x is any better, but I've never had issues. YMMV, but it doesn't take much more time and I like being thorough.
liquidzoo said:
Wipe data/factory reset is an option in CWM Recovery. Really all it does (from the screen messages) is format both /data and /cache.
Assuming you have CWM Recovery (though I imagine that there are similar entries in TWRP, I've just never used it), to wipe both of the caches you will first need to go to the entry "Wipe Cache Partition", which I believe is directly below Wipe Data/Factory Reset. Do that 3x (that's always been the recommendation, anyway) then go to Advanced and click on Wipe Dalvik Cache (again, 3x).
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Click to collapse
sorry, but can you confirm that when i upgrade to the new ROM (from the same author), it is really necessary to Wipe cache &Dalvik cache?
i am confused because somebody told me that i can just flash the ROM by installing the ZIP file (containing the ROM), and reboot the Nook without having to wipe or clean anything.
thanks,
JK
Flashing a ROM
junkoi said:
sorry, but can you confirm that when i upgrade to the new ROM (from the same author), it is really necessary to Wipe cache &Dalvik cache?
i am confused because somebody told me that i can just flash the ROM by installing the ZIP file (containing the ROM), and reboot the Nook without having to wipe or clean anything.
thanks,
JK
Click to expand...
Click to collapse
I don't know if I am doing it right or wrong but I have flashed numerous ROMs and lately have flashed every version of SGT7+CM10+Cherry Picks,By meghd00t. from 24/09 thru my current installation of 08/10 with only one glitch and that was when I flashed enhancements v2 on top of v1.
I have never had any other issues with the above mentioned ROMs except when I flashed 04/10 with enhancement v2. I didn't have the tablet option.
The way I do it is as follows:
1. format /system
2. format /data
3. Flash ROM
4. Flash CWM emmc
5. Flash GAPPs
6. Reset Factory/format data
7. Remove CWM SD card put in data SD Card with Flash Player (no longer avail on Google Play)
8. Boot from CWM menu
Takes awhile to boot this first time. When booted up I bypass the setup screens.
9. Manually set up wireless (need to access auth web site at work and need wireless to be working to accomplish that)
10. Browse to a web site and get redirected to auth page.
11. Auth
12. Set up Google account and other settings, especially under Security <Install from other locations>
13. Download apps I want from Google.
At this first boot SD card is not mounted.
14. Shut down and do a cold boot.
Now I can see SD Card.
15. Install Flash Player from External SD Card.
16. Install Crackle from Play Store.
Now I check Pandora for Audio, Crackle for Video, other apps I use, utilities, keyboards, launchers, games, etc.
So far since Version 24/09 everything has worked for me with the two exceptions above, tablet mode with 04/10 with enhancement v2 and when I flashed enhancement v2 over enhancement v1.
I am now running 08/10 and am very happy with the performance, battery drain is more than CM7 but that is to be expected from a fairly new ROM but not so bad that it is unacceptable, to me at least.
I have never had a black screen or arbitrary reboot (knock on wood). However I do turn my tablet off when I am finished using it, so don't know about deep sleep. I'm using OnDemand, and three launchers without one being the default....Apex, Nova and Trebucket.
All I can say is these developers really ROCK, way to go guys!
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MojoGB said:
The way I do it is as follows:
1. format /system
2. format /data
3. Flash ROM
4. Flash CWM emmc
5. Flash GAPPs
6. Reset Factory/format data
7. Remove CWM SD card put in data SD Card with Flash Player (no longer avail on Google Play)
8. Boot from CWM menu
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Click to collapse
You don't need to re-flash CWM every time you flash a ROM. Also, it doesn't make sense to me why you would do a factory reset/format after flashing the new ROM, I would think it would be done prior to flashing the ROM but maybe it doesn't make a difference, I don't know.
I've got TWRP installed to the emmc so I just download the new ROM to the SD with GooManager, reboot into recovery, do a backup, factory reset, flash new ROM & GApps and reboot. Only takes a few minutes.
Reflash ROM
LifeWOutMilk said:
You don't need to re-flash CWM every time you flash a ROM. Also, it doesn't make sense to me why you would do a factory reset/format after flashing the new ROM, I would think it would be done prior to flashing the ROM but maybe it doesn't make a difference, I don't know.
I've got TWRP installed to the emmc so I just download the new ROM to the SD with GooManager, reboot into recovery, do a backup, factory reset, flash new ROM & GApps and reboot. Only takes a few minutes.
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Click to collapse
Tried it as you mentioned, doing a factory reset before flashing the ROM and got a black screen and wouldn't boot. May have been a fluke but the way I mentioned above gives me a good image and alway boots. Don't know why, but if it works for me, I will continue to do it this way as long as it works for me. I have flashed numerous other ROMs the same way with good results each time.
junkoi said:
sorry, but can you confirm that when i upgrade to the new ROM (from the same author), it is really necessary to Wipe cache &Dalvik cache?
i am confused because somebody told me that i can just flash the ROM by installing the ZIP file (containing the ROM), and reboot the Nook without having to wipe or clean anything.
thanks,
JK
Click to expand...
Click to collapse
For an update, yes it is recommended to clear both caches. To be clear, this is only for an update. If it is a new ROM, or if the author recommends it, you should also wipe /data and /system first.
You can just flash without clearing them, but you might run into unexpected issues, so it's not recommended.
MojoGB said:
Tried it as you mentioned, doing a factory reset before flashing the ROM and got a black screen and wouldn't boot. May have been a fluke but the way I mentioned above gives me a good image and alway boots. Don't know why, but if it works for me, I will continue to do it this way as long as it works for me. I have flashed numerous other ROMs the same way with good results each time.
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I get a black screen for a while on first boot too, but it only last a couple minutes at the most and if you shine a bright light at the screen you can see the CM logo spinning. Are you sure it was hung?
Sent from my Barnes & Noble Nook Tablet using xda premium
When you clear the Dalvik cache, it clears out data stored in your applications. When you turn on your Nook after clearing the Dalvik, the first thing it does is it rebuilds the Dalvik cache, that's why it seemed like it hung on startup. I believe the long black screen in the beginning is when it rebuilds Dalvik for core Android apps and then when it says "Optimizing Apps", that's for the rest of your applications. The more apps you have, the longer it will take to build the Dalvik. No need to freak out, just a little patience is all you need. Correct me if I'm wrong, however, as I'm still pretty much a noob at this... :laugh:
Flash a Rom
topdawg7793 said:
When you clear the Dalvik cache, it cleares out data stored in your applications. When you turn on your Nook after clearing the Dalvik, the first thing it does is it rebuilds the Dalvik cache, that's why it seemed like it hung on startup. I believe the long black screen in the beginning is when it rebuilds dalvik for core Android apps and then when it says "Optimizing Apps", that's for the rest of your applications. The more apps you have, the longer it will take to build the dalvik. No need to freak out, just a little patience is all you need. Correct me if I'm wrong, however, as I'm still pretty much a noob at this... :laugh:
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Well fhe screen was black, no light at all and I waited for over five minutes for the Flash Screen to come up and it never did. Yes I know when you are waiting time drags. But due to the ROMS always taking awhile to boot up the first time I actually pay attention to how long it takes. No more then 2 minutes in my experience. I had to hold the power button in for a long time until it finally booted in B&N Recovery. Used my sequence mentioned in earlier post to flash the ROM again and everything worked as it should, GREAT. The number of APPs shouldn't be an issue as these ROMS only have the very basic apps.
I have read this forum and see the various and asundry errors some are getting, so far I have never gotten a major error, except for when I forgot to do the Wipe Data/Factory Reset after flashing.
I also got the "No Tablet Mode Option" with 04/10 with enhancement v2.
But I consider these minor issues and currently am running 08/10 with no issues, works smoother then any version of Microsoft Windows I have dealt with.
These developers are exceptional.
MojoGB said:
I don't know if I am doing it right or wrong but I have flashed numerous ROMs and lately have flashed every version of SGT7+CM10+Cherry Picks,By meghd00t. from 24/09 thru my current installation of 08/10 with only one glitch and that was when I flashed enhancements v2 on top of v1.
I have never had any other issues with the above mentioned ROMs except when I flashed 04/10 with enhancement v2. I didn't have the tablet option.
The way I do it is as follows:
1. format /system
2. format /data
3. Flash ROM
4. Flash CWM emmc
5. Flash GAPPs
6. Reset Factory/format data
7. Remove CWM SD card put in data SD Card with Flash Player (no longer avail on Google Play)
8. Boot from CWM menu
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Click to collapse
oh, so you always reset factory every time you upgrade the ROM? that way will delete all the old data/apps you installed, so you need to install all the apps again?
this is my concern, because i dont want to reinstall apps, or lose my data. so i think i just need flash the new ROM, then Wipe cache/Dalvik cache, and hopefully all the old apps and data are still intact.
thanks.
MojoGB said:
I don't know if I am doing it right or wrong but I have flashed numerous ROMs and lately have flashed every version of SGT7+CM10+Cherry Picks,By meghd00t. from 24/09 thru my current installation of 08/10 with only one glitch and that was when I flashed enhancements v2 on top of v1.
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Click to collapse
i have some questions on the "Enhancements":
(1) the correct way to install them is to flash version 1 first, then immediately flash version 2 right after version 1 (without having to reboot first)?
(2) i am not sure what i will get with this "enhancements". they will make video/audio playing more smoothly? is the quality improvement really noticable? anything else, like they make the battery last longer, for example?
thanks,
Jun
If you're running 08/10, the enhancements are not needed. That's my understanding at least. I had problems with V2 so I decided to not install them while on 04/10.
Sent from my Barnes & Noble Nook Tablet using xda premium
Flash Rom
junkoi said:
i have some questions on the "Enhancements":
(1) the correct way to install them is to flash version 1 first, then immediately flash version 2 right after version 1 (without having to reboot first)?
(2) i am not sure what i will get with this "enhancements". they will make video/audio playing more smoothly? is the quality improvement really noticable? anything else, like they make the battery last longer, for example?
thanks,
Jun
Click to expand...
Click to collapse
If you flash enhancement v2 on top of version 1 you will have problems, UI will stop. If you only flash v2 you will not have the Tablet Mode Option. So my understanding is that you can use either v1 or v2 but not both.
ROM 08/10 does not need either enhancement as indicated by the developer. ROM 08/10 works great by itself is my experience.
If I'm installing a ROM, backup the existing ROM and wipe everything.
If I'm installing a .zip package like GApps or an enhancement, backup the existing ROM, wipe Data/Dalvik.
Folks, these are development ROMS. Thar be bugs in thet thar code. It's going to take you longer than the time you think you're going to save by doing a dirty flash, and then having to restore the thing to stock (worse case) only to start all over.
Don't ask how I know.
wellersl said:
If I'm installing a ROM, backup the existing ROM and wipe everything.
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Click to collapse
so it is possible to back up the existing data/apps, then restore them back after the new ROM is flashed? could you please confirm this?
if so, how & what is the right steps to do the backup? can we still use CWM, or use ROM Manager, or other tools?
thanks
Hello!
Norwegian Noob here. I got the basics, nothing more.
I just used Link2SD to clean cache and to clean Dalvik Cache, and i may also have cleaned 2nd partition garbage.
Then i rebooted, and nothing happens. it just kept staying at the white "HTC" -screen over the night (gave it some time).
The morning after i went into CWM to wipe dalvik cache and clean cache. Then at reboot it needs some time (10min, i guess dalvik buildup?).
When its done and it gets to the "desktop", the apps just say "loading".
When i try to do something at all, i just get message saying for example "sorry, settings (process com.android.settings) stopped. try again".
Some apps can be used, like go sms pro, clockwidget, flashlightwidget, but no other apps like calculator, calendar, tapatalk.
Now if i try to reboot, it just keeps staying at the white HTC-screen. Then i have to take out battery, boot into recovery, delete dalvik cache again, and reboot. then the same thing happens again.
I would be happy for any suggestions i can get (and sorry for my bad english:laugh: )
My system:
HTC Desire A8181
Android 2.3
Cyanogen 7.2.0.1 (if i dont remember completely wrong, cant check as process crash)
Additional info; link2sd may have been automatically installed to SD, and may not have been moved to phone by me before i wiped dalvik via link2sd-settings.
No one with any suggestions?
Have to delete everything and install rom again if i cant solve this :-\
Sent from my GT-S5690 using Tapatalk 2
Sounds like you did more than delete just your cache and dalvik, couldn't say for sure but my guess is you have some apps or at least data installed in a partition you erased.
You will almost for surely need to wipe all and flash ROM or backup. You can try to fix permissions in recovery but I doubt it will help.
Sent from my Nexus 4 using xda premium