Serhiy Storchaka added the comment: Good catch Xiang Zhang! I missed this point. Here is fixed patch.
$ ./python -m perf timeit -s "d = dict.fromkeys(range(10**6))" -- "list(d)" Python 3.5: Median +- std dev: 33.8 ms +- 0.7 ms Python 3.6 unpatched: Median +- std dev: 37.8 ms +- 0.5 ms Python 3.6 patched: Median +- std dev: 34.0 ms +- 0.6 ms $ ./python -m perf timeit -s "d = dict.fromkeys(range(10**6)); v = d.values()" -- "list(v)" Python 3.5: Median +- std dev: 26.2 ms +- 0.7 ms Python 3.6 unpatched: Median +- std dev: 28.0 ms +- 0.6 ms Python 3.6 patched: Median +- std dev: 26.1 ms +- 0.8 ms $ ./python -m perf timeit -s "d = dict.fromkeys(range(10**6)); v = d.items()" -- "list(v)" Python 3.5: Median +- std dev: 232 ms +- 6 ms Python 3.6 unpatched: Median +- std dev: 259 ms +- 6 ms Python 3.6 patched: Median +- std dev: 249 ms +- 6 ms $ ./python -m perf timeit -s "d = dict.fromkeys(range(10**6))" -- "set(d)" Python 3.5: Median +- std dev: 68.3 ms +- 1.8 ms Python 3.6 unpatched: Median +- std dev: 68.1 ms +- 2.5 ms Python 3.6 patched: Median +- std dev: 63.7 ms +- 1.5 ms $ ./python -m perf timeit -s "from _testcapi import test_dict_iteration as t" -- "t()" Python 3.5: Median +- std dev: 3.31 ms +- 0.10 ms Python 3.6 unpatched: Median +- std dev: 3.51 ms +- 0.09 ms Python 3.6 patched: Median +- std dev: 3.43 ms +- 0.05 ms ---------- Added file: http://bugs.python.org/file44719/dict_iter2.patch _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue28183> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
