V8 JavaScript Engine – by Google

About V8

• V8 is Google’s open source JavaScript engine.
• V8 is written in C++ and is used in Google Chrome, the open source browser from Google.
• V8 implements ECMAScript as specified in ECMA-262, 3rd edition, and runs on Windows XP and Vista, Mac OS X 10.5 (Leopard), and Linux systems that use IA-32 or ARM processors.
• V8 can run standalone, or can be embedded into any C++ application

V8 is a new JavaScript engine specifically designed for fast execution of large JavaScript applications. In several benchmark tests, V8 is many times faster than JScript (in Internet Explorer), SpiderMonkey (in Firefox), and JavaScriptCore (in Safari). If your web application is bound by JavaScript execution speed, using V8 instead of your current JavaScript engine is likely to improve your application’s performance. How big the improvement is depends on how much JavaScript is executed and the nature of that JavaScript. For example, if the functions in your application tend to be run again and again, the performance improvement will be greater than if many different functions tend to run only once.

There are three key areas to V8’s performance:

• Fast Property Access
• Dynamic Machine Code Generation
• Efficient Garbage Collection