A program that's inherently single-threaded it's unlikely to benefit from more CPUs. When you say "any program" here, you mean "any program with >=8 threads", right?
Erlang, which btw. is older than Python, will perform better the more cores you have due to its message oriented nature. Python (2.7) on the other hand performed worse with multithreading on multicore.
I was hoping that Python would take the same direction in the future, but unfortunately we are getting the async/await mess, instead of a simple async object model (sorry, my pet peeve)
I could be wrong, but I think Py2.7 is about the same speed on multicore vs 1 core. Where did you get that idea?
The testcase is 100 threads sending 1000 messages in to each other in a ring. On a 8-core Mac Jython and IronPython performs better than on 1-core, but Python 2.7 performs so badly that it never finishes.
The ideal scenario is probably that the CPython interpreter starts one thread per core running as many coroutines in parallel as possible, but that looks like a long way away for Python