On Aug 10, 2011, at 6:15 AM, Nick Coghlan wrote: > On Wed, Aug 10, 2011 at 9:09 PM, David Beazley <d...@dabeaz.com> wrote: >> You're forgetting step 5. >> >> 5. Put fine-grain locks around all reference counting operations (or rewrite >> all of Python's memory management and garbage collection from scratch). > ... >> After implementing the aforementioned step 5, you will find that the >> performance of everything, including the threaded code, will be quite a bit >> worse. Frankly, this is probably the most significant obstacle to have any >> kind of GIL-less Python with reasonable performance. > > PyPy would actually make a significantly better basis for this kind of > experimentation, since they *don't* use reference counting for their > memory management. >
That's an experiment that would pretty interesting. I think the real question would boil down to what *else* do they have to lock to make everything work. Reference counting is a huge bottleneck for CPython to be sure, but it's definitely not the only issue that has to be addressed in making a free-threaded Python. Cheers, Dave _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
