Ars Technica Apple's custom ARM approach for A6 pays off in JavaScript performance
Apple's iPhone 5 is the fastest smartphone ever tested using the WebKit team's SunSpider JavaScript benchmark, apparently due to the custom core design of the A6 processor. The benchmark performs over twice as fast on the A6 as it does on the A5 processor in the iPhone 4S, and even bests smartphones running Intel's x86-based Atom processors, according to AnandTech.
AnandTech published an extensive SunSpider benchmark comparison on Wednesday morning, including results from an iPhone 5 test unit and two dozen other smartphones. The iPhone 5 turned in an impressive 914.7ms time, easily besting the 2250.0ms of the iPhone 4S—almost 2.5 times as fast. It also beat the current top Android device, Samsung's Galaxy SIII, which ran the benchmark in 1442.9ms. (The iPhone 5 is 1.6 times faster.)
It's important to note that SunSpider isn't the best measure of raw performance across platforms. JavaScript engines vary from browser to browser on different platforms, and Apple almost certainly employs optimizations in iOS that would be difficult to replicate in Android or WP7 on every available handset. However, it's notable that the iPhone 5's A6 processor is executing JavaScript significantly faster than the only Atom-based smartphone currently available, the Lava XOLO X900, which turned in a 1279.4ms score.