One of the speedbumps for Firefox right now is what happens when TraceMonkey can't trace (check out this post to find out more about what tracing is). Firefox falls back to its basic interpreter when JIT compilation isn't possible, and it's just not all that fast.Source: DownloadSquad
They're busily retooling what happens when those fallbacks occur, and early performance testing has yielded positive results. Where JägerMonkey can do its stuff, performance gains of 30-40% have been noted. Mozilla's Dave Mandelin like what he sees so far, reporting the "JägerMonkey implements enough JavaScript to run all of SunSpider in "Jäger mode" and is 18% faster than the interpreter." He adds, "And we haven't done that many optimizations yet–there are many more things we will do."
Firefox JägerMonkey JavaScript engine promises 30-40 percent performance gains
Posted on Sunday, February 28 2010 @ 20:12 CET by Thomas De Maesschalck