Android Enthusiasts Stack Exchange is a question and answer site for enthusiasts and power users of the Android operating system. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

When installing custom ROMs most recommend clearing the Dalvik cache. What exactly is Dalvik cache?

share|improve this question
up vote 23 down vote accepted

The Dalvik cache is the set of saved .dex files. A .dex file is basically a compiled bytecode version of an app that has been built for the Dalvik Virtual Machine on which Android's apps run. It's similar to the Java Virtual Machine and having saved .class files.

share|improve this answer
Is it thus normal for a freshly installed ROM with wiped Dalvik cache to take a long while to boot the first time? because ParanoidAndroid is sure taking its sweet time; five minutes and counting. – badp Apr 27 '13 at 6:35
@badp Yep, my first boots were often that long with various ROMs. I wouldn't give it too too long before assuming something's wrong though. – Matthew Read Apr 28 '13 at 1:25

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.