Google's newest test versions of Chrome are equipped with a faster JavaScript engine, an increasingly important browser component for running Web-based programs.

The result is faster-loading pages, more powerful Web applications, and another round in the browser performance competition with Microsoft's Internet Explorer, Mozilla's Firefox, Apple's Safari, and Opera.

Chrome Canary uses the new Crankshaft version of Google&39's JavaScript engine. On Mozilla&39's Kraken test, where shorter bars are better, it wins handily over the current stable version of Chrome. This and other tests are on a Dell Studio XPS 16 with a 1.73GHz Intel Q820 Core i7 processor and 6GB of memory.

The new JavaScript engine works better on Google&39's V8 benchmark, too.

On the SunSpider test, now in disfavor in some circles for being obsolete, the two browsers are tied.

Chrome's browser engine, called V8, is being upgraded to version 3, called Crankshaft. It uses a technique called adaptive compilation that translates JavaScript into native instructions for a processor and then concentrates more energy on improving the parts of the code used most often, Google said.

"Crankshaft uses adaptive compilation to improve both start-up time and peak performance. The idea is to heavily optimize code that is frequently executed and not waste time optimizing code that is not," Google programmers Kevin Millikin and Florian Schneider said yesterday in a company blog post.

The result: "pages that contain significant amounts of JavaScript code" load on average 12 percent faster, the programmers said. And when it comes to how fast JavaScript programs run once they're loaded, they said, "this is the biggest performance improvement since we launched Chrome in 2008."

JavaScript has become such a competitive feature among browsers that they're using brand names. Up against V8 is Microsoft's Chakra, debuting in IE9' Apple's Nitro' Opera's Carakan' and Mozilla's JaegerMonkey, debuting in Firefox 4.

JavaScript performance is important, but it's only one facet of browser quality. Others include support for new features such as WebGL's 3D graphics' the ability to accelerate display of graphics and text' privacy and security' how fast it can handle the increasingly important CSS (Cascading Style Sheets) technology for formatting' and performance of interacting with a Web page's DOM--or document object model, the hierarchical description of its elements.

All these areas and more are getting ever more attention. And if it wasn't clear what's at stake, look no further than Google's Chrome OS and Chrome Web Store. The first is a browser-based operating system that runs Web apps only' the second is a distribution mechanism to find and buy those apps.

There are plenty of uncertainties about how well Google will succeed in its ambition to transform the Web into a foundation for applications, not just static Web sites. But there are some things that aren't so unclear: more and more of people's work and personal life is being spent doing things within a browser. That trend is enabled by better performance and, at the same time, encourages even more advances.

The programmers specifically pointed to improvements in Gmail loading times, which I've found excruciatingly slow in recent months. However, my not-terribly-reliable stopwatch tests showed Crankshaft actually slower with that site: 2.4 seconds to load on an average of five runs loading Gmail on Chrome Canary 10.0.603.3 compared with 2.1 seconds for the newest stable version of Chrome, Chrome 8.0.552.215. Given the variability in the results (less than 2 seconds to more than 3), though, I wouldn't read too much into that result.

Of course, there are plenty of benchmarks for broader if more more artificial tests of JavaScript performance: Mozilla's Kraken (version 1.0), Google's V8 Benchmark (version 6), and WebKit's SunSpider (version 0.9.1).

Here, Crankshift definitely shows a difference, except on the SunSpider test whose influence has waned as browser makers' advancements have rendered it out of date. Bear in mind, though, that this was a test just on a single machine, a quad-core Dell Studio XPS 16 with 6GB of memory and that other machines will produce different results.

Browser benchmarks are a thorny issue. It's always tough to represent the full breadth of computing challenges in a single convenient test, and there's always the risk that engineers will design products for good benchmark scores even when the approach has little or no bearing on real-world work. Indeed, Firefox leveled benchmark engineering charges at Microsoft with IE9.

Chrome is gaining in popularity, on the verge of 10 percent of browser usage on the Web today for third place after IE and Firefox. It took years and a somewhat subversive effort to convince Google Chief Executive Eric Schmidt that the company should release a browser, but it's clearly a force to be reckoned with on the Net.