Android Enthusiasts Stack Exchange
Android Enthusiasts Stack Exchange

Questions tagged [dalvik]

Dalvik is the process virtual machine (VM) in Google's Android operating system. It is the software that runs the apps on Android devices. For optimization, the apps' Java Bytecode is compiled to Dalvik-compatible .dex (Dalvik Executable) files before installation on a device, which are stored in the so-called Dalvik Cache.

This tag is intended for questions concerning the Dalvik VM and, from the users point of view the most likely part of this, the Dalvik Cache.

More details on the Dalvik VM can be obtained e.g. from its Wikipedia article. Other useful ressources include e.g.:

Did you know...

...that there's also a Dalvik Turbo virtual machine, which is supposed to run up to 3 times faster than Googles Dalvik VM while consuming less battery?

69 questions
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Why Do I Need to Wipe Dalvik Cache?

When I'm updating a custom ROM, there's always an instruction to wipe the Dalvik cache. I don't see a reason why this is necessarily. Watching the logcat while the system is booting I can clearly see that if an app changed, its dex file is…
user13391
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What is Dalvik cache?

When installing custom ROMs most recommend clearing the Dalvik cache. What exactly is Dalvik cache?
GollyJer
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What kind of app optimizations do newer Android versions do at the first reboot?

I received from my phone carrier, Vodafone IT, the official OTA Google update to Android Ice Cream Sandwich 4.0.4 on my Nexus S. When automatically rebooting for the first time after the update, the system displayed a notice stating that it was…
Paolo Amoroso
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Manually switch from ART to Dalvik

I wanted to try out the new ART runtime, but didn't realize my custom ROM doesn't support it. So now I am getting recurring Force Closed messages after booting, and can't get through to the settings menu to switch back to Dalvik. So before I wipe…
David B.
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Dalvik VM vs. ART (Android Runtime): Impact for end-users?

With Nexus 5 (Android 4.4 KitKat), Google has shipped two runtimes to run apps. What are the differences between Dalvik & ART for endusers? How can endusers be affected by this? Is there any specific reason I should choose new ART runtime?
iOS Enthusiast
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Clear Caches from ADB?

How do I clear caches (app, individual apps, Dalvik, ART if possible) via ADB? Using apps, recovery, or doing it through Settings are not options for me. Also, my phone is not rooted.
LakeHMM
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How to keep the size of the Dalvik cache small?

I have an issue with the Dalvik cache getting huge and occupying almost all of the space on my phone. I'm running Cyanogenmod 7.X. For the record, I have about 5-6 small applications on my phone (keyboard, voice choice, Gmail, etc.), but I'm showing…
Naftuli Kay
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13
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What is the zygote process still doing in Android L?

I am trying to figure out the specific differences in the Dalvik and ART runtimes. I realize that ART no longer uses the Dalvik VM, however, one of the first things I noticed after installing the Android L preview was that the zygote process is…
John
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Why each android application runs on a different Dalvik VM process?

I have read that each android applications runs on a different Dalvik VM process (all forked from zygote). I also read that these VMs are really lightweight and use copy on write buffers and all that, so far so good. But, I also read that this was…
AndroidSec
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Can I change the dalvik cache location e.g. with a symbolic link?

I currently use Link2SD since my phone's onboard storage is insufficient for more than a few essential apps. It is very effective but limited to when the phone is on. While changing ROMs, the dalvik cache is wiped and when the phone restarts you see…
gontadu
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Clearing Dalvik Cache without root?

I recently tried updating my Motorola Atrix 4g. It downloaded, and then it booted down to try to update. However, instead of updating, it ends up booting to a screen that just says Failed to boot 2 Starting RSD mode If I take out the battery, I…
Ephraim
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Should Dalvik Cache be wiped in Android OS that supports ART?

When switching custom ROMs (in ART), is it necessary to wipe the Dalvik Cache? Wiping the Cache is necessary, but should wiping Dalvik (which doesn't exist in Android Lollipop and afterward) be necessary? What impact will it cause if we wipe Dalvik…
doylefermi
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Do calls to Java native interface in android apps run within Dalvik VM?

I read that apps sometimes access the native libraries for optimization purposes via the Java native interface. As far as I understand, JNI just provides java wrappers around c/c++ libraries/binaries which are written closer to hardware hence…
Sumesh Kumar
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How is the Android System running Java jars?

There is a large amount of Java jars in /system/framework, for example, am.jar. I understand that Android uses Java in a very confusing way (at least for me). I do not completely understand the way that dalvik works. Basically, I do not understand…
Tyler Richardson
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Nexus 5 has no settings to change runtime

I'm using Nexus 5. It was running on KitKat and I updated to Android L. I wanted to try and check out if it's running on Dalvik or ART, but the settings to change runtime in the Developer Option is not there. Does my phone have to be…
afwcxx
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