STINNER Victor <vstin...@python.org> added the comment:
> Would it not suffice to just make the singletons "immortal"? The problem is to make Py_INCREF/Py_DECREF efficient. Last time someone tried to use an atomic variable for ob_refcnt, it was 20% slower if I recall correctly. If many threads start to update such atomic variable, the CPU cacheline of common singletons like None, True and False can quickly become a performance bottleneck. On the other side, if each interpreter has its own objects, there is no need to protect ob_refcnt, the interpreter lock protects it. ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue39511> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
