performance difference between OSx and Windows

[Avizoa at gmail.com]

> Can I ask why that is, and if there is a way to take advantage
> of all 4 within python?

Sure. All major programming languages handle concurrency in one of two
ways: multithreading or parallel processes. In the standard python
interpreter, there is the Global Interpreter Lock (GIL for short) that
only allows one thread to run at once. So your option for python are
limited to running multiple processes or using a different interpreter.

What you are testing, however, is not easily parallizable since the
slow concat in particular is very dependent on sequential results. If
you want test the quad cores you'll have to run the test multiple times
with many different threads to truly stress them.