Posts tagged JIT

Ever wonder why applications running on Android handset don’t seem to running faster than those running on iPhone even the CPU used in the handset is much faster than the one used in iPhone?  That is because Android is using a virtual machine called Dalvik to run the Android applications.  It is similar to Java on desktop and some of the mobile phones.  Basically it is a software layer in the phone to provide an exactly same program execution environment to ensure same Android program is able to run on different Android phone even if the hardware and CPU are not the same.  However, since it is an additional layer, the application code will need to be translated all the time when it is being executed and this will normally mean the program will run slower than the native programs.

We are seeing light.  Company like Myriad (a member of OHA) has created a new virtual machine for Android called Dalvik Turbo and it promises to run the Dalvik code 2-3 times faster than the current Dalvik VM provided by stocked Android.  You can see the video below.  And at the same time, Google is working on a JIT (Just-In-Time compiler, it will compile the Dalvik code to native code during the start of the program execution) for the Android kernel and it is now in the experiment branch.  It is reported to boost the performance by 2-3 times also but it is not as stable as Dalvik Turbo for the moment.  However, we are seeing progress from Google.

So do expect performance boost for Android applications once we see Android handsets that come with Dalvik Turbo or when Google releases a stable version of the JIT.