Performance Benchmarks: JavaScript
Unfortunately, at the time of final testing, JSBenchmark, a regular component of the WBGP, was offline.
Kraken
Firefox 4 finishes first in the Kraken JavaScript benchmark, more than 500 milliseconds ahead of Chrome. In third place, Opera takes twice the time to finish as FF4. Finishing about 1500 milliseconds behind Opera is IE9, with Apple Safari taking 450 ms more than Microsoft's browser, putting it in last place.
SunSpider
IE9 again takes the top spot in SunSpider, almost 25 ms ahead of newcomer Firefox 4. Chrome finishes the test a fraction of a millisecond behind FF4 to place third. Right behind Chrome is Opera in fourth, with Safari taking over 60 ms longer than Opera to finish last.
V8 Benchmark
We're continuing to monitor the behavior of the V8 benchmark. Unfortunately, since JSBenchmark is not available to compare against, we won't be absolutely sure V8 is not a ringer for Google.
Chrome again slaughters the competition in Google's V8 test suite, earning more than twice the score of second-place finisher Firefox 4. Opera scores a third-place finish just behind Mozilla Firefox. Safari earns about 1300 points less than the Norwegian Web browser to place fourth, which leaves WBGP3 champ IE9 in last place.
It's not so much the placing generated by this test that bothers us, or even the fact that Chrome usually wins; it's the scale of Chrome's win. When JSBenchmark is included, it typically mirrors the placing of V8, but by much more reasonable margins. We're only leaving the V8 score in this time because JSBenchmark is down. Otherwise, it's safe to say we're over this one.
As usual, the JavaScript benchmarks are a mixed bag, with one win each from Chrome, Firefox, and Internet Explorer. Taking into account the total placing and margins of victory (other than Chrome in V8), it's Firefox 4 that leads in this discipline, though Chrome is right up there as well. Opera is now the middle-of-the-road option in JS speed, and IE9's performance is inconsistent. At this point, the aging Safari 5 is significantly slower than the competition.