Build me a JIT as fast as you can… [Squeak COG VM]

I've been using his VM in production for 6 months or so now. I haven't been happy with Squeak Smalltalk in a fast-paced production environment... however it has been fun for other reasons.<p>The actual language of Smalltalk is pretty nice and it is fun to read through posts like this because the simplicity of the language allows for easy learning of different algorithms. The underlying algorithms are pretty transparent.<p>It also makes it relatively easy to read through code to figure out what's going on and you learn a lot about implementation details by doing this.<p>Edit: forgot to mention, his Cog VM is pretty nice! It definitely helped improve performance of the system as a whole from slow &#38; pokey to feeling quick and more modern.

There was a submission to HN awhile back, where someone did a study of what actually happens with dynamic languages in JIT VMs. In many cases, there is a lot of dynamic behavior when an app server starts up, but later on, the system settles down, there's no fluidity in type information, and the system might as well be statically typed.<p>App server farms running hundreds of processes with instrumented JIT VMs could gather a lot of data. This would allow programmers to determine the "steady-state" type behavior of an app server after the "warm-up" period with a high degree of certainty. Would it be possible to save such data as an aggregation of runtime-profiles that could be used to 1) speed up execution and 2) back-port static type annotations to the source code? I could also imagine a special command to tell the VM that "warm-up" time is over now, take type annotations as mandatory, and start aggressive compiling now!

Here's a small benchmark that show COG VM improvements over standard Squeak VM and other commercial available Smalltalks: <a href="http://fbanados.wordpress.com/2011/02/10/a-tinybenchmark/" rel="nofollow">http://fbanados.wordpress.com/2011/02/10/a-tinybenchmark/</a>