Author: Armin Rigo <ar...@tunes.org> Branch: extradoc Changeset: r4032:6b30ed03026f Date: 2012-01-13 17:52 +0100 http://bitbucket.org/pypy/extradoc/changeset/6b30ed03026f/
Log: expand the introduction diff --git a/blog/draft/tm.rst b/blog/draft/tm.rst --- a/blog/draft/tm.rst +++ b/blog/draft/tm.rst @@ -11,16 +11,25 @@ PyPy to safely run multi-threaded programs: it is a global lock that prevents multiple threads from actually running at the same time. The reason to do that is that it would have disastrous effects in the -interpreter if both threads access the same object concurrently --- to +interpreter if several threads access the same object concurrently --- to the point that in CPython even just manipulating the object's reference counter needs to be protected by the lock. -So far, the ultimate goal to enable true multi-CPU usage has been to remove -the infamous GIL from the interpreter, so that multiple threads could actually -run in parallel. But we think we have a plan to implement a -different model for using multiple cores. Believe it or not, this is -*better* than just removing the GIL from PyPy. You might get to use all -your cores *without ever writing threads.* +So far, the ultimate goal to enable true multi-CPU usage has been to +remove the infamous GIL from the interpreter, so that multiple threads +could actually run in parallel. It's a lot of work, but this has been +done in Jython. The reason that it has not been done in CPython so far +is that it's even more work: we would need to care not only about +carefully adding fine-grained locks everywhere, but also about reference +counting; and there are a lot more C extension modules that would need +care, too. And we don't have locking primitives as performant as +Java's, which have been hand-tuned since ages (e.g. to use help from the +JIT compiler). + +But we think we have a plan to implement a different model for using +multiple cores. Believe it or not, this is *better* than just removing +the GIL from PyPy. You might get to use all your cores *without ever +writing threads.* You would instead just use some event dispatcher, say from Twisted, from Stackless, or from your favorite GUI; or just write your own. From _______________________________________________ pypy-commit mailing list pypy-commit@python.org http://mail.python.org/mailman/listinfo/pypy-commit
