The PyPy FAQ[1] says: "Operating system-level threads basically work. If you enable the thread module then PyPy will get support for GIL based threading." I ha

The PyPy FAQ[1] says: "Operating system-level threads basically work. If you enable the thread module then PyPy will get support for GIL based threading." I had hoped that because PyPy uses a more sophisticated garbage-collector than CPython, it wouldn't need locking to update reference counts and hence wouldn't need a GIL (or wouldn't use it as much); I guess that's not the case (at least yet). [1]: http://codespeak.net/pypy/dist/pypy/doc/faq.html#do-threads-work-what-are-the-modules-that-work http://codespeak.net/pypy/dist/pypy/doc/faq.html#do-threads-...