Mozilla has unleashed the Kraken, a new JavaScript benchmark test.

It joins similar efforts like Google’s V8 and the WebKit project’s SunSpider tests, which are widely used to measure browser performance. However, unlike V8 and SunSpider, which are more general stress tests to measure overall capability, Mozilla’s Rob Sayre says Kraken focuses mainly on “realistic workloads and forward-looking applications.”

Among the real-world things Kraken tests are Mozilla’s new beat detection scripts, which uses experimental audio APIs, and image processing tools like the ones that apply a Gaussian blur or desaturate a JPG using JavaScript.

“These are the things that people are saying are too slow to do with open web technologies today,” Sayre writes, “and we want to have benchmarks that reflect progress against making these near-future apps universally available.”

While real-world tests are important and Kraken offers a way to measure browser performance in ways that aren’t really possible without it, in terms of an overall performance benchmark test, Kraken seems unlikely to supplant V8 or SunSpider.

Of course, supplanting doesn’t seem to be the goal of Kraken. Rather, Mozilla wants to shift focus from generalized benchmarks to tests that reflect what’s actually happening on the web — both today’s web apps and those that are pushing the boundaries and paving the way for a new generation of apps.

The goal of Kraken is less about proving how “fast” a browser is overall and more about offering a way to test actual, everyday tasks that mirror the things we all do with web browsers.

To test Kraken you can head over to the new site and run it yourself. In Mozilla’s testing Kraken shows that Firefox 4 (with its new JaegerMonkey JavaScript engine) is already more than 2.5 times faster than the current release of Firefox 3.6.

See Also:

• New HTML5 Tools Make Your Browser Sing and Dance
• Firefox 4 Beta 5 Adds Audio Tools, Hardware Acceleration
• Firefox JaegerMonkey Builds Are Available