It was an unpleasant surprise to see results of Javascript performance for Firefox 3.5.6 running under openSUSE 11.2 64bit. Running SunSpider JavaScript benchmark (SunSpider JavaScript Benchmark) took 4808 ms. One would expect that running the same test for IE8, FF 3.6 and Google Chrome 4.0.249 under XP in VirtualBox would yield somewhat close results. According to Firefox 3.6 performance JS performance of FF 3.6 is about 16% than FF 3.5, so considering VirtualBox overhead, the results should be somewhat close, I thought.
FF 3.5.6 under openSUSE 11.2 64bit: 4808ms
FF 3.6 under Win XP inside VB: 1321ms
Chrome 4.0 under Win XP inside VB: 715ms
IE8 under Win XP inside VB: 8348ms
Are there any reasons when FF would be so much slower? Maybe it is not optimized to work with 64bit OS?
Does anyone have any ideas how to improve it?