There are a lot of other performance reasons for the .dex format that I didn't see in your article. For example, in Java byte code each class is in its own file inside of the zip. In Dalvik, they are all in one .dex file. This makes it a lot faster to start the app (all code is loaded at once), and greatly reduces the overall size because it can do things like pool all strings together.
Also the dex format is designed to be very easy to turn into the final .odex file -- this the result of doing the final link of the .dex against the platform it is running on. And the .odex file (and thus dex file) is designed so that to load it you can just mmap it. Using mmap greatly reduces memory pressure because the kernel can freely map and unmap pages as it wants (and remember we don't use a swap file so if the code is loaded into an allocation it can never be paged out of RAM). On Thu, Oct 27, 2011 at 3:09 AM, Mark Murphy <[email protected]>wrote: > http://commonsware.com/blog/Articles/what-is-dalvik.html > > On Thu, Oct 27, 2011 at 6:06 AM, bob <[email protected]> wrote: > > What is the point of putting stuff in this weird Dalvik format? Why > > not use Java bytecode? > > > > -- > > You received this message because you are subscribed to the Google > > Groups "Android Developers" group. > > To post to this group, send email to [email protected] > > To unsubscribe from this group, send email to > > [email protected] > > For more options, visit this group at > > http://groups.google.com/group/android-developers?hl=en > > > > > > -- > Mark Murphy (a Commons Guy) > http://commonsware.com | http://github.com/commonsguy > http://commonsware.com/blog | http://twitter.com/commonsguy > > Android Training in NYC: http://marakana.com/training/android/ > > -- > You received this message because you are subscribed to the Google > Groups "Android Developers" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/android-developers?hl=en > -- Dianne Hackborn Android framework engineer [email protected] Note: please don't send private questions to me, as I don't have time to provide private support, and so won't reply to such e-mails. All such questions should be posted on public forums, where I and others can see and answer them. -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
