Guido's asked me to give a quick status report, so here I go.. The critical parts of the design and implementation are basically done. I've implemented monitors to contain objects without an explicit thread-safe API, which then let me remove the GIL. I've created a synchronous/asynchronous refcounting scheme that reuses our existing INCREF/DECREF API, but also minimizes contention when used by more than one thread. The net result is that although there's a significant amount of overhead, I can demonstrate scalability to more than one thread (I've only been able to test with two cores though.)
I've replaced __del__ API (which resurrected objects) with a __finalize__/__finalizeattrs__ API (which doesn't). Attributes listed in __finalizeattrs__ are proxied into a core object, a finalizer thread is given a reference to the core, and when the main object is deleted the GC asynchronously notifies the finalizer thread so that it can call core.__finalize__(). The net result is an API very similar to __del__ (you need to list attributes it might use), but it's now impossible for the GC to run arbitrary code (I even enforce this). Missing there is generator cleanup. I don't allow the GC to run a generator long enough to raise GeneratorExit, so an alternative will be needed. I'm currently working on flushing out the design. I recently rewrote and reenabled the tracing GC, next up is the automatic deadlock detection/breaking. As for merging back into CPython, I could build smaller patches, but the design can't be completely separated. For example, __finalize__ is called from another thread, so Monitor's @monitormethod should be applied. I don't specifically require Monitor, just that the object (and therefor its methods) be shareable, and Monitor is the easiest way to provide that. -- Adam Olsen, aka Rhamphoryncus _______________________________________________ Python-3000 mailing list Python-3000@python.org http://mail.python.org/mailman/listinfo/python-3000 Unsubscribe: http://mail.python.org/mailman/options/python-3000/archive%40mail-archive.com
