Java is desirable because a developer can write a program once, and then have it executed on any hardware platform that has a working interpreter (the Java Virtual Machine). The other prime example of interpreted code is Java - and Dalvik is essentially Google’s version of Java. (You can happily run JavaScript on any platform that has a modern web browser - you can’t run a Windows EXE on Apple’s OS X.) Interpreted code is useful for two primary reasons: You can make changes without having to recompile the whole thing, and because it’s platform agnostic.

The most common example of interpreted code is JavaScript, which your web browser interprets/compiles whenever you visit a website that uses JavaScript. This can come in many varieties, but the main thing is that interpreted code cannot be directly executed by the CPU - it must first be compiled by the interpreter into machine code, using a process called just-in-time compilation (JIT). The other kind of code is interpreted code. Windows, your web browser, Crysis 3, Linux, iOS apps - these are all examples of compiled code.īig-budget AAA games like Crysis are nearly always compiled, for performance reasons. If you open an EXE file, you see compiled code - gobbledegook machine code that your CPU can execute. Compiled code is source code that has been compiled, by the developer, into code that the computer can understand (machine code). When you run software on a computer, such as a PC or smartphone, you are nearly always running compiled code. The early version of ART in Android 4.4 already speeds up apps by around 100%, and the final version should be even better. Now, with Android 4.4, Google has revealed that a Dalvik replacement is in the works - a replacement, called Android Runtime (ART), that should improve the performance of Android apps by a huge margin.

Everything, that is, except for the most important part: Dalvik, the virtual machine that runs almost every Android app, has remained virtually the same since day one - and Dalvik is slow.

Throughout the rapid and tumultuous history of Android, which is now five years old, almost every aspect of the OS has been changed, updated, or overhauled in some way.

Android dalvik vm