The browser speed war appeared to be pretty much over, until a few days ago, when Mozilla's JIT compiler lead David Mandelin sent out a tweet that the new JIT IonMonkey has eclipsed Chrome in at least one configuration on Mozilla's Kraken benchmark.
Posted on Mozilla's AreWeFastYet page - which was originally established when Mozilla began working on JaegerMonkey (that arrived with Firefox 4 and is still in use today) - Firefox 17 with IonMonkey squeezes the win with a performance of 1991 ms versus Chrome's 2038 ms. Mandelin notes that this result is achieved on a Mac Pro with a 32-bit version of the browser.
Of course, JavaScript benchmarks were interesting two years ago and it seems we have largely lost interest in the millisecond race, but I was nevertheless interested in those claims. In the end, Mozilla promised in 2009 that it would try to catch up with Chrome and if it can do it now, even if it is a bit late, it's noteworthy since it kept its promise.
I was not able to replicate the claim on my venerable Phenom II X6 Windows 7 system. Chrome won with 3349 ms versus 3715 ms for Firefox. However, IonMonkey gained almost 20 percent of speed over the current JaegerMonkey in Firefox 15 beta, which came in at 4627 ms. Perhaps there is still some room left for faster JavaScript engines?
