We actually compared stock lua to luajit in production, for something with high load and serious performance requirements. The difference turned out to be no b

We actually compared stock lua to luajit in production, for something with high load and serious performance requirements. The difference turned out to be no big deal, less than x2 in speed. The real performance killer seems to be garbage collection and chasing pointers due to inefficient data structures. Luajit doesn't help much here. In the end we went with stock lua because it doesn't have the 1 gigabyte memory limit, and so can use a much larger thread pool.