Firefox to get JavaScript boost

Firefox's occasionally lacklustre JavaScript performance is set to be a thing of the past thanks to a new engine under development: JägerMonkey.

JägerMonkey - also known as JaegerMonkey - is a marriage between a modern, fast Just-In-Time (JIT) compiler alongside the TraceMonkey engine which was developed for Firefox 3.5. While current versions of Firefox rely on the TraceMonkey engine - which attempts to find the most-used code fragments in a site and compiles them into native code for a massive boost in speed - for their performance, the underlying engine that is used in the event that TraceMonkey is unable to do its magic doesn't really stand up to comparison with the performance from rivals such as Chrome and Opera.

Mozilla's David Anderson didn't think that relying on TraceMonkey was enough. Quoted over on Softpedia as asking "Why couldn’t we trace and keep going SUPER AWESOME FAST, and when tracing fails, fall back to STILL REALLY FAST," Anderson has been working on improving the underlying JIT JavaScript engine in Firefox for when TraceMonkey is unable to compile the native code segments.

While the project is in the first stages of development at the moment - expect to see something in Firefox 4.0 at the absolute earliest - the new JIT compiler Anderson has developed is currently performing around 30 percent faster on 32-bit hardware and a whopping 45 percent faster on 64-bit hardware than its predecessor. Further development by the Mozilla team on the native-code assembler used by TraceMonkey - Apple's Nitro compiler - is also yielding gains of around 18 percent.

Once the two are joined together, Anderson predicts "a much more consistent – and fast – JavaScript performance experience."

With JavaScript performance perhaps being the true test of a modern browser, with barely a single page on the 'net not using some JavaScript code to perform clever tasks, it's about time that Mozilla did something about its performance in cases where TraceMonkey can't be used.

Are you excited to see that the gap between Firefox and its competitors is narrowing, or do you think there are more important things that the Mozilla Foundation needs to concentrate on before worrying about JavaScript performance? Share your thoughts over in the forums.