New submission from STINNER Victor: Attached patch changes index(), insert() and rotate() functions of the collections.deque type to use FASTCALL calling convention. I chose to only modify these functions since they use METH_VARARGS which requires to create a temporary tuple, whereas other functions use METH_NOARGS or METH_O which is already fast ;-)
I know that Raymond, maintainer of the collections module, is not a big fan of Argument Clinic ;-) So I wrote the minimum change and chose to not use Argument Clinic yet. By the way, the index() method has the signature "D.index(value, [start, [stop]])" which is not supported by Argument Clinic yet: see issue #29299. For these reasons, I propose to wait to convert collections.deque to Argument Clinic, it can be done later. Ok, now the cool part: it makes these methods faster ;-) * d.rotate(): 1.10x faster * d.rotate(1): 1.24x faster * d.insert(): 1.18x faster * d.index(): 1.24x faster $ ./python -m perf timeit -s 'import collections; d=collections.deque()' 'd.rotate()' --compare-to=../default-ref/python Median +- std dev: [ref] 70.5 ns +- 0.9 ns -> [patch] 64.2 ns +- 0.3 ns: 1.10x faster (-9%) $ ./python -m perf timeit -s 'import collections; d=collections.deque()' 'd.rotate(1)' --compare-to=../default-ref/python Median +- std dev: [ref] 107 ns +- 1 ns -> [patch] 86.2 ns +- 1.1 ns: 1.24x faster (-20%) $ ./python -m perf timeit -s 'import collections' 'd=collections.deque(); d.insert(0, None); d.insert(1, None); d.insert(2, None); d.insert(3, None); d.insert(4, None)' --compare-to=../default-ref/python -p3 Median +- std dev: [ref] 699 ns +- 6 ns -> [patch] 591 ns +- 5 ns: 1.18x faster (-15%) $ ./python -m perf timeit -s 'import collections; d=collections.deque((None,))' 'd.index(None)' --compare-to=../default-ref/python Median +- std dev: [ref] 115 ns +- 1 ns -> [patch] 92.5 ns +- 0.8 ns: 1.24x faster (-19%) ---------- files: deque.patch keywords: patch messages: 287044 nosy: haypo, rhettinger, serhiy.storchaka priority: normal severity: normal status: open title: Use FASTCALL for collections.deque methods: index, insert, rotate type: performance versions: Python 3.7 Added file: http://bugs.python.org/file46523/deque.patch _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue29452> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
