Nexus 5 (ART) vs Nexus 5 (Dalvik)(Video)
A quick overview of what ART is and why you might want to install it. Any app on Android has to be compiled (translated to run on the device from the raw app code) to run on your device. The program that does this compiling at the moment on Android is called JIT (just in time) and it compiles the Android app as you open it (just in time making more sense now?). This has its benefits as it allows less storage to be needed on the device (since the compiling takes place every time the app is opened and the code is discarded every time it’s closed) but the major draw back of this is that it takes a bit to compile and that produces that lag you feel when opening an app.
Since storage has become much cheaper than when Android originally came out, Google decided to start working on a new runtime program that would compile the code once when you install the app instead of having to do it every time the app is opened. This new runtime is called ART. After two years of working on it, they’ve put it in Android 4.4. The runtime isn’t active by default, however (still ironing out some things and improving it), but you can easily activate it from the settings if you want to check it out. Before you do, keep in mind Google’s own words on the matter:
ART is a new Android runtime being introduced experimentally in the 4.4 release KitKat. This is a preview of work in progress in KitKat. It is available for the purpose of obtaining early developer and partner feedback.
To enable ART head to our How to Enable ART video.
With that background and disclaimer from Google, we wanted to see how much of a real world difference ART makes over JIT. So in this video we run some simple tests including boot time, web browsing, and opening various popular apps (where the ART should technically make it’s big difference). Here’s what happened.
Share your thoughts below!
Did you previously open the apps, etc. with ART before measuring the timings? ART should be faster only on the second or later openings of each app since it still must compile the code for the first run. Once compiled, ART should be faster for most applications, but it will not be faster on the first run of the app.
I believe it compiles when it installs the app. Which is why it takes longer to install apps with ART installed.
@connor is right. It compiles when installing not on the first opening.