I know what happens when you do a factory reset/wipe, but what exactly happens if I only wipe Dalvik Cache? (I'm about to flash a ROM, don't want to do a complete factory reset/wipe, but wondering if I can still help "eliminate ghosts" by wiping Dalvik Cache.)
Bump, is this just like a crazy question or something?
What exactly does wiping Dalvik cache do?
trunkstar1 said:
Bump, is this just like a crazy question or something?
What exactly does wiping Dalvik cache do?
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Click to collapse
dalvik is a virtual machine in android operating system that runs applications, which is similar java vm. dalvik builds some sort of cache of applications (i wouldn't go into details) to run them faster in dalvik cache space. you can clear them out, and android will rebuild the cache on the next boot. and the initial boot will take longer than usual once you wiped the dalvik cache because android needs to rebuild it.
So it's something that you can safely wipe on occasion right, just to clear up any bugs?
trunkstar1 said:
So it's something that you can safely wipe on occasion right, just to clear up any bugs?
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Click to collapse
when you flash a custom rom, usually the rom automatically wipes out dalvik cache to remove all that junk from the previous rom.. you do not need to wipe it regularly unless you flash apps or any other system modifications on top of the existing rom via clockworkmod recovery very often
But is there any "harm" in doing it? Any consequences other than a longer reboot time?
trunkstar1 said:
But is there any "harm" in doing it? Any consequences other than a longer reboot time?
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Not at all. Apps will just be a little sluggish for a bit.
Sent from my SGH-T959 using XDA App
Using Kies to goto 2.2, does that wipes Dalvik cache? Koz I went to 2.2 from kies mini, then ODIN'd a Voodoo kernel and i never wiped it manually...
so should I?
many thanks
You are trying to not factory reset but any rom you will find will have a system, data, data_data and cache wipe built into it. You can try finding a Rom you like and remove the wipes from the update_script but those wipes are put there on purpose. Kies will wipe everything too.
or use root explorer go in to system and find dalvik cache and delete files =>
sir can i ask a question?
jaetm83 said:
dalvik is a virtual machine in android operating system that runs applications, which is similar java vm. dalvik builds some sort of cache of applications (i wouldn't go into details) to run them faster in dalvik cache space. you can clear them out, and android will rebuild the cache on the next boot. and the initial boot will take longer than usual once you wiped the dalvik cache because android needs to rebuild it.
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Click to collapse
is it normal to boot so long when i accidentally wipe dalvik cache? because im afraid and thinking my phone was brick what can i do to turn it back normal? wait to boot the system?
avie14 said:
is it normal to boot so long when i accidentally wipe dalvik cache? because im afraid and thinking my phone was brick what can i do to turn it back normal? wait to boot the system?
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Click to collapse
Yes it is normal for it to take longer than a normal bootup. It is rebuilding the Dalvik that was just wiped. #nosorcery
trunkstar1 said:
I know what happens when you do a factory reset/wipe, but what exactly happens if I only wipe Dalvik Cache? (I'm about to flash a ROM, don't want to do a complete factory reset/wipe, but wondering if I can still help "eliminate ghosts" by wiping Dalvik Cache.)
Click to expand...
Click to collapse
Thank you for this question, thank you guys now I know that wiping dalvik cache is not that bad at all.
I recently flashed aokp carbon rom on my galaxy sl.
But the performance is weak. Is there any general settings for all aokp rom which will increase performance ? In the rom control option i go to scrolling cache if i need best scrolling what should i set it to
Force enable
Default enable
Default disable
or Force disable ?
thank you guys sorry i am noob
Default enable should do. If that still doesn't improve scrolling, try force enable. Just try the options for yourself and see, that's the best way. You need to give more details about your issue. Elaborate on the 'weak' performance. Also, did you wipe cache & dalvik cache before installing the ROM?
Sent from my Desire HD using xda premium
No i was on cm9 before so i did not wipe anything. i directly installled. should i wipe dalvik cache and cache , factory reset ?
now i am on aokp so can i reinstall it again after wiping cche and dalvik cache ? will it mprove the perfomace ?
Change the kernel
sorry but there is only one kernel for ics any other suggestion ?
Yes. You should always wipe dalvik cache and cache when installing a new ROM. Even if it's just a version update of an already installed ROM. It's always better to wipe to avoid usual FC problems. Dalvik cache mainly. The only thing is that your phone will take around 5-6 minutes to boot the first time after you wipe dalvik cache, because it's rebuilding the cache. After that it'll boot normally every other time until you wipe dalvik cache again.
CM9 and AOKP are two different ROMs so when changing between them you should do a full wipe i.e. wipe everything (system, data, cache, dalvik cache and .android_secure folder on the SD card). Otherwise you'll get a lot of FCs. If you do a full wipe all your apps will be gone so you might want to take a Titanium Backup of them or just set them up again when they re-download automatically on the new ROM. Make sure to not restore data of any system apps using Titanium Backup in the new ROM. Once you install the AOKP ROM, upgrading to a newer version won't need a full wipe but only dalvik cache and cache wipe.
About the kernel, just use the one that came with your ROM.
Sent from my Desire HD using xda premium
wiping cache/dalvik are a must when flashing any new kernels
I was getting out of space on my internal phone, so I decided to clear wipe cache and dalvik cache through CWM, but I find i save a lot of space BUT some apps stop working, maybe they are lost. So was does this actually do? Why are the apps there, but can't work? :crying:
Ok, after rebooting they are actually working again, i didn't even lost any data (progress on games) but I am really concerned what does this really do??
rolo143 said:
I was getting out of space on my internal phone, so I decided to clear wipe cache and dalvik cache through CWM, but I find i save a lot of space BUT some apps stop working, maybe they are lost. So was does this actually do? Why are the apps there, but can't work? :crying:
Ok, after rebooting they are actually working again, i didn't even lost any data (progress on games) but I am really concerned what does this really do??
Click to expand...
Click to collapse
http://en.wikipedia.org/wiki/Dalvik_(software)
When you reboot, Dalvik cache and Cache are re-created. So no space saved this way.
Feanor88 said:
http://en.wikipedia.org/wiki/Dalvik_(software)
When you reboot, Dalvik cache and Cache are re-created. So no space saved this way.
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Click to collapse
I was wondering what wiping the Dalvik cache did, too. I installed an inverted app and someone told me I needed to wipe the Dalvik cache in order for it to remain in place after a reboot, so I did that. Now my phone says "Optimizing apps..." It must rbe e-creating the cache.
As far as I know, when a rom boots up for the first time Dalvik goes through each & every apk's & extract the Dex & put it in the cache. So probably it is a location of all apks. If dalvik cache is not wiped after a new rom is installed,dalvik cache will skip because it founds the dexed cache files attach to the directory. The result is "Force close" issues.
So wiping dalvik cache can be done without any problem many times within the same rom & that's why is shows "optiming apps" after a dalvik cache wipe.
saqib nazm said:
As far as I know, when a rom boots up for the first time Dalvik goes through each & every apk's & extract the Dex & put it in the cache. So probably it is a location of all apks. If dalvik cache is not wiped after a new rom is installed,dalvik cache will skip because it founds the dexed cache files attach to the directory. The result is "Force close" issues.
So wiping dalvik cache can be done without any problem many times within the same rom & that's why is shows "optiming apps" after a dalvik cache wipe.
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Thanks! That's in line with my suspicion, except I didn't know when I posted my question that an apk file was nothing but a zip file that contains a dex (Dalvik executable) and a bunch of other files. Your explanation makes sense. I also noticed that if I install an individual app from a zip file using CWM Recovery, then it clears the relevant part of the Dalvik cache for me. That doesn't happen when I install an apk file directly using Root Explorer.
guys one line question i am performing "Wipe cache and dalvik-cache" will my phone internal memory be deleted ? thanks a ton
deepankarbu said:
guys one line question i am performing "Wipe cache and dalvik-cache" will my phone internal memory be deleted ? thanks a ton
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Click to collapse
Nop, it will not
Sent from my SK17i using xda premium
Phone didn't boot after wiping Dalvik Cache
Hi Geeks
i have an Xperia Arc S modded with Cyanogenmod JellyBean 4.1.2 Cooked ROM
i had alot of memory issues as applications keep closing whenever system runs out of memory, it is always obvious in the DSP application with the walkman in addition to visualizations inside the walkman
i searched for a solution and some told me that wiping the dalvik cache might solve the problem, so i gave it a try and rebooted in CWM recovery mode "built inside ROM" , cleared the Dalvik cache , and the phone keeps displaying the Xperia Logo without any further progress, as if it's in somekinda loop !
any idea what to do next without wiping my Data ? thank you all
BR
AMR
Koptanov said:
Hi Geeks
i have an Xperia Arc S modded with Cyanogenmod JellyBean 4.1.2 Cooked ROM
i had alot of memory issues as applications keep closing whenever system runs out of memory, it is always obvious in the DSP application with the walkman in addition to visualizations inside the walkman
i searched for a solution and some told me that wiping the dalvik cache might solve the problem, so i gave it a try and rebooted in CWM recovery mode "built inside ROM" , cleared the Dalvik cache , and the phone keeps displaying the Xperia Logo without any further progress, as if it's in somekinda loop !
any idea what to do next without wiping my Data ? thank you all
BR
AMR
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Click to collapse
Are you sure you only wiped the dalvik?
Sent from Myushi
clears app cache
rolo143 said:
I was getting out of space on my internal phone, so I decided to clear wipe cache and dalvik cache through CWM, but I find i save a lot of space BUT some apps stop working, maybe they are lost. So was does this actually do? Why are the apps there, but can't work? :crying:
Ok, after rebooting they are actually working again, i didn't even lost any data (progress on games) but I am really concerned what does this really do??
Click to expand...
Click to collapse
it clears the app running cache stored in os.
absolutely ..
XperienceD said:
Are you sure you only wiped the dalvik?
Sent from Myushi
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Yes sir it's only the dalvik cache, both ways this ROM was pretty heavy and i'm not satisfied with the reboot every 2 or 3 hours of use, i will install xperia ultimate HD ROM, they say it's pretty stable and has no problems, and it has the sound enhancements i needed in the Jellybean cooked ROM
thanks for your reply
alcatel 918n
XperienceD said:
Are you sure you only wiped the dalvik?
Sent from Myushi
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Click to collapse
My phone also has those options built-in. If you did the dalvik only it should get back to where you have the icons. BUT, if you did something else aside from the dalvik, my guess would be goodbye data and hello to phone repairs. Please research first before you do anything on your phone. Your phone and my phone have very powerful built-in tools. It could brick the phone. I hope you did not wipe data and flash.
help! my phone's boot taking too long
i wiped /cache and dalvik cache and format /cache. it's taking took long. been waiting for almost 1 hour.
Lucky Patcher Dalvik-cache
I am getting out of space msg when using Lucky Patcher.....apk will be patched on boot......it says to clear dalvik cache to save space.....is this a good idea(will I loose any data from game etc?) or this a issue with lucky patcher?
Clearing Dalvik
Feanor88 said:
When you reboot, Dalvik cache and Cache are re-created. So no space saved this way.
Click to expand...
Click to collapse
Um, that would involve the re- "optimization" process at each boot. Depending on the number of apps you have installed, this process can take an hour.
Simply put, the Dalvik cache is where a virtual machine program (like VMware Player, Workstation or Fusion or MSVM) called "Dalvik" stores information the applications on your device request it to. This storage is for the purpose of making app load times shorter, but because it's all low-level stuff, it has to be loaded prior to the AndroidOS frontend...Fortunately, this cache only needs to be rebuilt when a flag has been set indicating the need, which is set whenever the cache is cleared. Note the distinction between "loading" and "rebuilding" this cache. "Load" is synonymous with "read" and "rebuild" means "write." So time-wise it is the distinction in effort between reading a book and writing one.
Typically I only clear it for troubleshooting reasons; if something is not working. The latest Cyanogenmod has a major problem where the desktop data is liable to randomly corrupt.
Typically, the only solution is a Dalvik wipe in CM or whatever. If you have recently installed a large number of apps(over twenty)then it might be best to clear the cache via recovery at the next cold boot, especially if your device does weird stuff like getting hot, discharging while plugged in to the OEM charger, widgets crash spontaneously, wallpapers are replaced by defaults, etc....Some of these symptoms can also indicate a virus or malware infection,(especially on custom ROMs or rooted devices) so diagnosis is differential.
But essentially there is no harm in re-building the Dalvik cache, other than the time taken to do so.
Koptanov said:
Yes sir it's only the dalvik cache, both ways this ROM was pretty heavy and i'm not satisfied with the reboot every 2 or 3 hours of use, i will install xperia ultimate HD ROM, they say it's pretty stable and has no problems, and it has the sound enhancements i needed in the Jellybean cooked ROM
thanks for your reply
Click to expand...
Click to collapse
CM has this new MAJOR stability issue, it seems. The random crashes and reboots will soon combine(if they haven't already)with the deletion of your desktop customizations and your widgets will begin vanishing forever. Not even a full wipe and rebuild will bring them back.
Been using AOKP on Nexus 7 2013 for a month now. It is based on CM, but it is way more stable.....haven't needed to re-boot in two weeks! Uptime, baby!
UPDATE 04/05/2014: Been running without rebooting for over a month, now. AOKP is definitely WAY more stable than any other ROM I've used.
Dalvik explained
Saqib Nazm said:
As far as I know, when a rom boots up for the first time Dalvik goes through each & every apk's & extract the Dex & put it in the cache. So probably it is a location of all apks. If dalvik cache is not wiped after a new rom is installed,dalvik cache will skip because it founds the dexed cache files attach to the directory. The result is "Force close" issues.
So wiping dalvik cache can be done without any problem many times within the same rom & that's why is shows "optiming apps" after a dalvik cache wipe.
Click to expand...
Click to collapse
There is a full explanation of the dalvik cache on wikipedia.
The wiki entry fully explains dalvik cache and the integral part it plays in your android system. In very simple terms, it is a cache that allows the system to talk to the exe of a program without the need to load the cache on each and every start. The dalvik is is loaded once, and then never again (unless you wipe the dalvik cache, in which case, it is rebuilt upon reboot). There is no affect on any given program when the dalvik cache is wiped, other than starting slower the first time it is started after the wipe.
Related (I think) - Samsung Galaxy S5 running CM 12.1 latest nightly (6-14). I started on CM 12.0 nightlies in March or April and transitioned to 12.1 within a day or two acter it showed up. That was a relatively noticeable transition requiring new gapps and a factory reset as I recall. I read somewhere that wiping cache and dalvik cache was unnecessary between one 12.0 nightly to another and between one 12.1 nightly to another, so I typically have not performed the cache and dalvik wipe during nightly upgrades, of which I've probably done 30 or 40 since I started on 12.0. After each nightly update flash, when I ask TWRP to reboot the system, without wipes, all my 160 or so apps are optimized, taking some time, before the noot is compete. This morning out of curiosity, after the nee ROM was flashed, I chose the option in TWRP to wipe the cache and dalvik cache before I askefasked TWRP to reboot the system. The wipe process took at least as long to complete as a typical optimization, and when I rebooted, I still got the lengthy optimization. So I'm tbinking either there's no relationship berween app optimization and wiping the caches, or CM and/or TWRP automatically wipes the caches whether I do or not.
---------- Post added at 12:58 PM ---------- Previous post was at 12:54 PM ----------
Please forgive typos in my previous post - SwiftKey or something is making proofreading and editing difficult today.
Not the exact answer, but may interests u.
Koptanov said:
Hi Geeks
i have an Xperia Arc S modded with Cyanogenmod JellyBean 4.1.2 Cooked ROM
i had alot of memory issues as applications keep closing whenever system runs out of memory, it is always obvious in the DSP application with the walkman in addition to visualizations inside the walkman
AMR
Click to expand...
Click to collapse
Hi, I do not have the exact answer. But I wanted to share my own observation. When I wipe dalvik caches through CWM recovery, I find my phone taking a long time to finish booting every time. Sometimes I thought it would not boot up, I removed the battery and tried to swith on and my phone boots up. I do not know why it happens, may be I had installed a large no of apps.
I've got Nexus 5 with bootloader unlocked , after few weeks security patch arrived and after the phone switched off and showed error symbol and when I entered recovery mode it showed that error in system/bin.sh files need some help here
I have just updated my device from 2.3.5 to 4.3. The installation instructions didn't mention what I should clear after upgrade (dalvik, data, battery stats, etc). So should I clear any of them?
mcnamaragio said:
I have just updated my device from 2.3.5 to 4.3. The installation instructions didn't mention what I should clear after upgrade (dalvik, data, battery stats, etc). So should I clear any of them?
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Not a bad idea to clear data, if you have a backup.
At the least, I'd suggest you clear Cache and Davlik. Battery stats don't matter much.
Should I have cleared them before flashing the rom? If I clear them now will I have to reflash the phone?
mcnamaragio said:
Should I have cleared them before flashing the rom? If I clear them now will I have to reflash the phone?
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Click to collapse
No you can clear it after too, only data will be cleared, but the rom will still be on your phone.
I would advise you to clear data, dalvik cache and cache partition between gingerbread and ics (or any new major release for that matter), as well as wipe battery stats and fix permissions.
Between small updates within the same version just clearing dalvik cache is enough.