[issue44022] urllib http client possible infinite loop on a 100 Continue response
Change by Sergey Fedoseev : -- nosy: +sir-sigurd nosy_count: 8.0 -> 9.0 pull_requests: +25593 pull_request: https://github.com/python/cpython/pull/27033 ___ Python tracker <https://bugs.python.org/issue44022> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue39759] os.getenv documentation is misleading
Change by Sergey Fedoseev : -- nosy: +sir-sigurd ___ Python tracker <https://bugs.python.org/issue39759> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue33239] tempfile module: functions with the 'buffering' option are incorrectly documented
Change by Sergey Fedoseev : -- nosy: +sir-sigurd nosy_count: 4.0 -> 5.0 pull_requests: +21279 pull_request: https://github.com/python/cpython/pull/21763 ___ Python tracker <https://bugs.python.org/issue33239> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue35276] Document thread safety
Change by Sergey Fedoseev : -- nosy: +sir-sigurd ___ Python tracker <https://bugs.python.org/issue35276> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue26834] Add truncated SHA512/224 and SHA512/256
Change by Sergey Fedoseev : -- nosy: +sir-sigurd ___ Python tracker <https://bugs.python.org/issue26834> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue41415] duplicated signature of dataclass in help()
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +20793 stage: -> patch review pull_request: https://github.com/python/cpython/pull/21652 ___ Python tracker <https://bugs.python.org/issue41415> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue41415] duplicated signature of dataclass in help()
New submission from Sergey Fedoseev : In [191]: import dataclasses, pydoc In [192]: @dataclass ...: class C: ...: pass ...: In [193]: print(pydoc.render_doc(C)) Python Library Documentation: class C in module __main__ class C(builtins.object) | C() -> None | | C() | | Methods defined here: | It's duplicated because dataclass __doc__ defaults to signature: In [195]: C.__doc__ Out[195]: 'C()' -- components: Library (Lib) messages: 374461 nosy: sir-sigurd priority: normal severity: normal status: open title: duplicated signature of dataclass in help() type: behavior versions: Python 3.10 ___ Python tracker <https://bugs.python.org/issue41415> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue41141] remove unneeded handling of '.' and '..' from patlib.Path.iterdir()
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +20336 stage: -> patch review pull_request: https://github.com/python/cpython/pull/21179 ___ Python tracker <https://bugs.python.org/issue41141> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue41141] remove unneeded handling of '.' and '..' from patlib.Path.iterdir()
New submission from Sergey Fedoseev : Currently patlib.Path.iterdir() filters out '.' and '..'. It's unneeded since patlib.Path.iterdir() uses os.listdir() under the hood, which returns neither '.' nor '..'. https://docs.python.org/3/library/os.html#os.listdir -- components: Library (Lib) messages: 372465 nosy: sir-sigurd priority: normal severity: normal status: open title: remove unneeded handling of '.' and '..' from patlib.Path.iterdir() ___ Python tracker <https://bugs.python.org/issue41141> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue40302] Add pycore_byteswap.h internal header file with _Py_bswap32() function
Change by Sergey Fedoseev : -- nosy: +sir-sigurd nosy_count: 3.0 -> 4.0 pull_requests: +19338 pull_request: https://github.com/python/cpython/pull/15659 ___ Python tracker <https://bugs.python.org/issue40302> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue27961] remove support for platforms without "long long"
Change by Sergey Fedoseev : -- pull_requests: +17021 pull_request: https://github.com/python/cpython/pull/17539 ___ Python tracker <https://bugs.python.org/issue27961> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37347] Reference-counting problem in sqlite
Change by Sergey Fedoseev : -- pull_requests: +16894 pull_request: https://github.com/python/cpython/pull/17413 ___ Python tracker <https://bugs.python.org/issue37347> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue38524] functools.cached_property is not supported for setattr
Change by Sergey Fedoseev : -- nosy: +sir-sigurd ___ Python tracker <https://bugs.python.org/issue38524> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue38517] functools.cached_property should support partial functions and partialmethod's
Sergey Fedoseev added the comment: issue38524 is related. -- nosy: +sir-sigurd ___ Python tracker <https://bugs.python.org/issue38517> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue35696] remove unnecessary operation in long_compare()
Sergey Fedoseev added the comment: These warnings are caused by https://github.com/python/cpython/commit/c6734ee7c55add5fdc2c821729ed5f67e237a096. I'd fix them, but I'm not sure if we are going to restore CHECK_SMALL_INT() ¯\_(ツ)_/¯ -- nosy: +sir-sigurd ___ Python tracker <https://bugs.python.org/issue35696> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue38147] add macro for __builtin_unreachable
Sergey Fedoseev added the comment: > If you care of _PyLong_Copy() performance, you should somehow manually inline > _PyLong_New() inside _PyLong_Copy(). It doesn't solve this: > We could add a function that bypass that check, but in LTO build > PyObject_MALLOC() is inlined into _PyLong_New() and it also checks the size. > Adding Py_ASSUME((size_t)size <= MAX_LONG_DIGITS) allows to bypass both > checks. Here's example: https://github.com/sir-sigurd/cpython/commit/c8699d0c614a18d558216ae7d432107147c95c28. I attach some disassembly from this example compiled with LTO, to demonstrate how the proposed macro affects generated code. -- Added file: https://bugs.python.org/file48614/disasm.txt ___ Python tracker <https://bugs.python.org/issue38147> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue38205] Py_UNREACHABLE() no longer behaves as a function call
Sergey Fedoseev added the comment: FWIW I proposed to add Py_ASSUME() macro that uses __builtin_unreachable() in bpo-38147. -- ___ Python tracker <https://bugs.python.org/issue38205> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue38211] clean up type_init()
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +15852 stage: -> patch review pull_request: https://github.com/python/cpython/pull/16257 ___ Python tracker <https://bugs.python.org/issue38211> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue38211] clean up type_init()
New submission from Sergey Fedoseev : I wrote patch that cleans up type_init(): 1. Removes conditions already checked by assert() 2. Removes object_init() call that effectively creates an empty tuple and checks that this tuple is empty -- messages: 352710 nosy: sir-sigurd priority: normal severity: normal status: open title: clean up type_init() ___ Python tracker <https://bugs.python.org/issue38211> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue38205] Python no longer compiles without small integer singletons
Sergey Fedoseev added the comment: Also quote from Py_UNREACHABLE() doc: > Use this in places where you might be tempted to put an assert(0) or abort() > call. https://github.com/python/cpython/commit/6b519985d23bd0f0bd072b5d5d5f2c60a81a19f2 does exactly that, it replaces assert(0) with Py_UNREACHABLE(). -- ___ Python tracker <https://bugs.python.org/issue38205> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue38205] Python no longer compiles without small integer singletons
Sergey Fedoseev added the comment: I believe that the problem is caused by the change in Py_UNREACHABLE() (https://github.com/python/cpython/commit/3ab61473ba7f3dca32d779ec2766a4faa0657923). Before the mentioned commit Py_UNREACHABLE() was an expression, now it's a block. Py_UNREACHABLE() macro is public (see https://docs.python.org/3/c-api/intro.html#c.Py_UNREACHABLE), so this change can cause similar problems outside of CPython (i.e. that change was breaking). -- nosy: +sir-sigurd ___ Python tracker <https://bugs.python.org/issue38205> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue38147] add macro for __builtin_unreachable
New submission from Sergey Fedoseev : GCC (along with Clang and ICC) has __builtin_unreachable() and MSVC has __assume() builtins, that can be used to optimize out unreachable conditions. So we could add macro like this: #ifdef Py_DEBUG # define Py_ASSUME(cond) (assert(cond)) #else # if defined(_MSC_VER) # define Py_ASSUME(cond) (__assume(cond)) # elif defined(__GNUC__) # define Py_ASSUME(cond) (cond? (void)0: __builtin_unreachable()) # else # define Py_ASSUME(cond) ((void)0); # endif #endif Here's a pair of really simple examples showing how it can optimize code: https://godbolt.org/z/g9LYXF. Real world example. _PyLong_Copy() [1] calls _PyLong_New() [2]. _PyLong_New() checks the size, so that overflow does not occur. This check is redundant when _PyLong_New() is called from _PyLong_Copy(). We could add a function that bypass that check, but in LTO build PyObject_MALLOC() is inlined into _PyLong_New() and it also checks the size. Adding Py_ASSUME((size_t)size <= MAX_LONG_DIGITS) allows to bypass both checks. [1] https://github.com/python/cpython/blob/3a4f66707e824ef3a8384827590ebaa6ca463dc0/Objects/longobject.c#L287-L309 [2] https://github.com/python/cpython/blob/3a4f66707e824ef3a8384827590ebaa6ca463dc0/Objects/longobject.c#L264-L283 -- messages: 352228 nosy: sir-sigurd priority: normal severity: normal status: open title: add macro for __builtin_unreachable ___ Python tracker <https://bugs.python.org/issue38147> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue38094] unneeded assignment to wb.len in PyBytes_Concat using buffer protocol
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +15517 stage: -> patch review pull_request: https://github.com/python/cpython/pull/15274 ___ Python tracker <https://bugs.python.org/issue38094> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue38079] _PyObject_VAR_SIZE should avoid arithmetic overflow
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +15471 stage: -> patch review pull_request: https://github.com/python/cpython/pull/14838 ___ Python tracker <https://bugs.python.org/issue38079> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue38015] inline function generates slightly inefficient machine code
Sergey Fedoseev added the comment: I use GCC 9.2. -- ___ Python tracker <https://bugs.python.org/issue38015> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue38015] inline function generates slightly inefficient machine code
Sergey Fedoseev added the comment: I added similar patch that replaces get_small_int() with macro version, since it also induces unnecessary casts and makes machine code less efficient. Example assembly can be checked at https://godbolt.org/z/1SjG3E. This change produces tiny, but measurable speed-up for handling small ints: $ python -m pyperf timeit -s "from collections import deque; consume = deque(maxlen=0).extend; r = range(256)" "consume(r)" --compare-to=../cpython-master/venv/bin/python --duplicate=1000 /home/sergey/tmp/cpython-master/venv/bin/python: . 1.03 us +- 0.08 us /home/sergey/tmp/cpython-dev/venv/bin/python: . 973 ns +- 18 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 1.03 us +- 0.08 us -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 973 ns +- 18 ns: 1.05x faster (-5%) -- ___ Python tracker <https://bugs.python.org/issue38015> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue38015] inline function generates slightly inefficient machine code
Change by Sergey Fedoseev : -- pull_requests: +15372 pull_request: https://github.com/python/cpython/pull/15718 ___ Python tracker <https://bugs.python.org/issue38015> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37986] Improve perfomance of PyLong_FromDouble()
New submission from Sergey Fedoseev : This patch simplifies fast path for floats that fit into C long and moves it from float.__trunc__ to PyLong_FromDouble(). +-+-+--+ | Benchmark | long-from-float-ref | long-from-float | +=+=+==+ | int(1.) | 39.5 ns | 37.3 ns: 1.06x faster (-6%) | +-+-+--+ | int(2.**20) | 46.4 ns | 45.6 ns: 1.02x faster (-2%) | +-+-+--+ | int(2.**30) | 52.5 ns | 49.0 ns: 1.07x faster (-7%) | +-+-+--+ | int(2.**60) | 50.0 ns | 49.2 ns: 1.02x faster (-2%) | +-+-+--+ | int(-2.**63)| 76.6 ns | 48.6 ns: 1.58x faster (-37%) | +-+-+--+ | int(2.**80) | 77.1 ns | 72.5 ns: 1.06x faster (-6%) | +-+-+--+ | int(2.**120)| 91.5 ns | 87.7 ns: 1.04x faster (-4%) | +-+-+--+ | math.ceil(1.) | 57.4 ns | 32.9 ns: 1.74x faster (-43%) | +-+-+--+ | math.ceil(2.**20) | 60.5 ns | 41.3 ns: 1.47x faster (-32%) | +-+-+--+ | math.ceil(2.**30) | 64.2 ns | 43.9 ns: 1.46x faster (-32%) | +-+-+--+ | math.ceil(2.**60) | 66.3 ns | 42.3 ns: 1.57x faster (-36%) | +-+-+--+ | math.ceil(-2.**63) | 67.7 ns | 43.1 ns: 1.57x faster (-36%) | +-+-+--+ | math.ceil(2.**80) | 66.6 ns | 65.6 ns: 1.01x faster (-1%) | +-+-+--+ | math.ceil(2.**120) | 79.9 ns | 80.5 ns: 1.01x slower (+1%) | +-+-+--+ | math.floor(1.) | 58.4 ns | 31.2 ns: 1.87x faster (-47%) | +-+-+--+ | math.floor(2.**20) | 61.0 ns | 39.6 ns: 1.54x faster (-35%) | +-+-+--+ | math.floor(2.**30) | 64.2 ns | 43.9 ns: 1.46x faster (-32%) | +-+-+--+ | math.floor(2.**60) | 62.1 ns | 40.1 ns: 1.55x faster (-35%) | +-+-+--+ | math.floor(-2.**63) | 64.1 ns | 39.9 ns: 1.61x faster (-38%) | +-+-+--+ | math.floor(2.**80) | 62.2 ns | 62.7 ns: 1.01x slower (+1%) | +-+-+--+ | math.floor(2.**120) | 77.0 ns | 77.8 ns: 1.01x slower (+1%) | +-+-+--+ I'm going to speed-up conversion of larger floats in a follow-up PR. -- components: Interpreter Core files: bench-long-from-float.py messages: 350861 nosy: sir-sigurd priority: normal pull_requests: 15285 severity: normal status: open title: Improve perfomance of PyLong_FromDouble() type: performance versions: Python 3.9 Added file: https://bugs.python.org/file48573/bench-long-from-float.py ___ Python tracker <https://bugs.python.org/issue37986> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37976] zip() shadows TypeError raised in __iter__() of source iterable
Sergey Fedoseev added the comment: > map() does not have anything special. Just for the reference, in Python 2.7 map() has the same behavior and it caused many problems for me and other people working with/developing Django. -- ___ Python tracker <https://bugs.python.org/issue37976> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37976] zip() shadows TypeError raised in __iter__() of source iterable
Sergey Fedoseev added the comment:
Also using this example class:
In [5]: iter(Iterable('one'))
---
TypeError Traceback (most recent call last)
in ()
> 1 iter(Iterable('one'))
in __iter__(self)
3 self.n = n
4 def __iter__(self):
> 5 return iter(range(self.n))
6
TypeError: range() integer end argument expected, got str.
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[issue37976] zip() shadows TypeError raised in __iter__() of source iterable
Sergey Fedoseev added the comment: Maybe it's not clear from description, but traceback only show the line with zip(), so it doesn't help at localizing the source of exception at all. You only see that 'argument #N must support iteration', but that argument has __iter__() i.e. it supports iteration. -- ___ Python tracker <https://bugs.python.org/issue37976> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37976] zip() shadows TypeError raised in __iter__() of source iterable
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +15268 stage: -> patch review pull_request: https://github.com/python/cpython/pull/15592 ___ Python tracker <https://bugs.python.org/issue37976> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37976] zip() shadows TypeError raised in __iter__() of source iterable
New submission from Sergey Fedoseev :
zip() shadows TypeError raised in __iter__() of source iterable:
In [21]: class Iterable:
...: def __init__(self, n):
...: self.n = n
...: def __iter__(self):
...: return iter(range(self.n))
...:
In [22]: zip(Iterable('one'))
---
TypeError Traceback (most recent call last)
in ()
> 1 zip(Iterable('one'))
TypeError: zip argument #1 must support iteration
--
messages: 350763
nosy: sir-sigurd
priority: normal
severity: normal
status: open
title: zip() shadows TypeError raised in __iter__() of source iterable
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[issue37974] zip() docstring should say 'iterator' instead of 'object with __next__()'
New submission from Sergey Fedoseev : In [3]: help(zip) class zip(object) | zip(*iterables) --> zip object | | Return a zip object whose .__next__() method returns a tuple where | the i-th element comes from the i-th iterable argument. The .__next__() | method continues until the shortest iterable in the argument sequence | is exhausted and then it raises StopIteration. This description is awkward and should use term 'iterator' as https://docs.python.org/3/library/functions.html#zip does. The same applies to chain(), count() and zip_longest() from itertools. -- assignee: docs@python components: Documentation messages: 350704 nosy: docs@python, sir-sigurd priority: normal severity: normal status: open title: zip() docstring should say 'iterator' instead of 'object with __next__()' ___ Python tracker <https://bugs.python.org/issue37974> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37973] improve docstrings of sys.float_info
New submission from Sergey Fedoseev : In [8]: help(sys.float_info) ... | | dig | DBL_DIG -- digits | This is not very helpful, https://docs.python.org/3/library/sys.html#sys.float_info is more verbose, so probably docstrings should be updated from where. -- assignee: docs@python components: Documentation messages: 350703 nosy: docs@python, sir-sigurd priority: normal severity: normal status: open title: improve docstrings of sys.float_info type: enhancement ___ Python tracker <https://bugs.python.org/issue37973> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37837] add internal _PyLong_FromUnsignedChar() function
Sergey Fedoseev added the comment: These last results are invalid :-) I thought that I was checking _PyLong_FromUnsignedChar() on top of GH-15192, but that wasn't true. So the correct results for LTO build are: $ python -m perf timeit -s "from collections import deque; consume = deque(maxlen=0).extend; b = bytes(2**20)" "consume(b)" --compare-to=../cpython-master/venv/bin/python /home/sergey/tmp/cpython-master/venv/bin/python: . 6.93 ms +- 0.04 ms /home/sergey/tmp/cpython-dev/venv/bin/python: . 3.96 ms +- 0.01 ms Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 6.93 ms +- 0.04 ms -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 3.96 ms +- 0.01 ms: 1.75x faster (-43%) But the most important thing is that using PyLong_FromUnsignedLong() instead of _PyLong_FromUnsignedChar() on top of GH-15192 is producing the same results: striter_next() uses small_ints[] directly. However that's not true for bytearrayiter_next(): PyLong_FromUnsignedLong() is called there. I think that's due to how code is profiled so I'm satisfied with these results more or less. I'm closing existing PR and probably will close this issue soon after GH-15192 will be merged. -- ___ Python tracker <https://bugs.python.org/issue37837> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37802] micro-optimization of PyLong_FromSize_t()
Sergey Fedoseev added the comment: Previous benchmarks results were obtained with non-LTO build. Here are results for LTO build: $ python -m perf timeit -s "from itertools import repeat; _len = repeat(None, 0).__length_hint__" "_len()" --compare-to=../cpython-master/venv/bin/python --duplicate=1000 /home/sergey/tmp/cpython-master/venv/bin/python: . 14.9 ns +- 0.2 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 13.1 ns +- 0.5 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 14.9 ns +- 0.2 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 13.1 ns +- 0.5 ns: 1.13x faster (-12%) $ python -m perf timeit -s "from itertools import repeat; _len = repeat(None, 2**10).__length_hint__" "_len()" --compare-to=../cpython-master/venv/bin/python --duplicate=1000 /home/sergey/tmp/cpython-master/venv/bin/python: . 22.1 ns +- 0.1 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 20.9 ns +- 0.4 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 22.1 ns +- 0.1 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 20.9 ns +- 0.4 ns: 1.05x faster (-5%) $ python -m perf timeit -s "from itertools import repeat; _len = repeat(None, 2**30).__length_hint__" "_len()" --compare-to=../cpython-master/venv/bin/python --duplicate=1000 /home/sergey/tmp/cpython-master/venv/bin/python: . 23.3 ns +- 0.0 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 21.6 ns +- 0.1 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 23.3 ns +- 0.0 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 21.6 ns +- 0.1 ns: 1.08x faster (-8%) $ python -m perf timeit -s "from itertools import repeat; _len = repeat(None, 2**60).__length_hint__" "_len()" --compare-to=../cpython-master/venv/bin/python --duplicate=1000 /home/sergey/tmp/cpython-master/venv/bin/python: . 24.4 ns +- 0.1 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 22.7 ns +- 0.1 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 24.4 ns +- 0.1 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 22.7 ns +- 0.1 ns: 1.08x faster (-7%) -- ___ Python tracker <https://bugs.python.org/issue37802> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37837] add internal _PyLong_FromUnsignedChar() function
Sergey Fedoseev added the comment: $ gcc -v 2>&1 | grep 'gcc version' gcc version 8.3.0 (Debian 8.3.0-19) using ./configure --enable-optimizations --with-lto $ python -m perf timeit -s "from collections import deque; consume = deque(maxlen=0).extend; b = bytes(2**20)" "consume(b)" --compare-to=../cpython-master/venv/bin/python /home/sergey/tmp/cpython-master/venv/bin/python: . 6.71 ms +- 0.09 ms /home/sergey/tmp/cpython-dev/venv/bin/python: . 6.71 ms +- 0.08 ms Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 6.71 ms +- 0.09 ms -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 6.71 ms +- 0.08 ms: 1.00x slower (+0%) using ./configure --enable-optimizations $ python -m perf timeit -s "from collections import deque; consume = deque(maxlen=0).extend; b = bytes(2**20)" "consume(b)" --compare-to=../cpython-master/venv/bin/python /home/sergey/tmp/cpython-master/venv/bin/python: . 6.73 ms +- 0.17 ms /home/sergey/tmp/cpython-dev/venv/bin/python: . 4.28 ms +- 0.01 ms Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 6.73 ms +- 0.17 ms -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 4.28 ms +- 0.01 ms: 1.57x faster (-36%) -- ___ Python tracker <https://bugs.python.org/issue37837> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37938] refactor PyLong_As*() functions
New submission from Sergey Fedoseev : PyLong_As*() functions have a lot of duplicated code, creating draft PR with attempt to deduplicate them. -- components: Interpreter Core messages: 350367 nosy: sir-sigurd priority: normal severity: normal status: open title: refactor PyLong_As*() functions ___ Python tracker <https://bugs.python.org/issue37938> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37938] refactor PyLong_As*() functions
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +15152 stage: -> patch review pull_request: https://github.com/python/cpython/pull/15457 ___ Python tracker <https://bugs.python.org/issue37938> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue27961] remove support for platforms without "long long"
Change by Sergey Fedoseev : -- pull_requests: +15098 pull_request: https://github.com/python/cpython/pull/15388 ___ Python tracker <https://bugs.python.org/issue27961> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue27961] remove support for platforms without "long long"
Change by Sergey Fedoseev : -- pull_requests: +15095 pull_request: https://github.com/python/cpython/pull/15386 ___ Python tracker <https://bugs.python.org/issue27961> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue27961] remove support for platforms without "long long"
Change by Sergey Fedoseev : -- pull_requests: +15094 pull_request: https://github.com/python/cpython/pull/15385 ___ Python tracker <https://bugs.python.org/issue27961> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37907] speed-up PyLong_As*() for large longs
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +15074 stage: -> patch review pull_request: https://github.com/python/cpython/pull/15363 ___ Python tracker <https://bugs.python.org/issue37907> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37907] speed-up PyLong_As*() for large longs
New submission from Sergey Fedoseev :
PyLong_As*() functions computes result for large longs like this:
size_t x, prev;
x = 0;
while (--i >= 0) {
prev = x;
x = (x << PyLong_SHIFT) | v->ob_digit[i];
if ((x >> PyLong_SHIFT) != prev) {
*overflow = sign;
goto exit;
}
}
It can be rewritten like this:
size_t x = 0;
while (--i >= 0) {
if (x > (size_t)-1 >> PyLong_SHIFT) {
goto overflow;
}
x = (x << PyLong_SHIFT) | v->ob_digit[i];
}
This provides some speed-up:
PyLong_AsSsize_t()
$ python -m perf timeit -s "from struct import Struct; N = 1000; pack =
Struct('n'*N).pack; values = (2**30,)*N" "pack(*values)"
--compare-to=../cpython-master/venv/bin/python
/home/sergey/tmp/cpython-master/venv/bin/python: . 9.69 us
+- 0.02 us
/home/sergey/tmp/cpython-dev/venv/bin/python: . 8.61 us +-
0.07 us
Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 9.69 us +-
0.02 us -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 8.61 us +- 0.07 us:
1.12x faster (-11%)
PyLong_AsSize_t()
$ python -m perf timeit -s "from struct import Struct; N = 1000; pack =
Struct('N'*N).pack; values = (2**30,)*N" "pack(*values)"
--compare-to=../cpython-master/venv/bin/python
/home/sergey/tmp/cpython-master/venv/bin/python: . 10.5 us
+- 0.1 us
/home/sergey/tmp/cpython-dev/venv/bin/python: . 8.19 us +-
0.17 us
Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 10.5 us +-
0.1 us -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 8.19 us +- 0.17 us:
1.29x faster (-22%)
PyLong_AsLong()
$ python -m perf timeit -s "from struct import Struct; N = 1000; pack =
Struct('l'*N).pack; values = (2**30,)*N" "pack(*values)"
--compare-to=../cpython-master/venv/bin/python
/home/sergey/tmp/cpython-master/venv/bin/python: . 9.68 us
+- 0.02 us
/home/sergey/tmp/cpython-dev/venv/bin/python: . 8.48 us +-
0.22 us
Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 9.68 us +-
0.02 us -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 8.48 us +- 0.22 us:
1.14x faster (-12%)
PyLong_AsUnsignedLong()
$ python -m perf timeit -s "from struct import Struct; N = 1000; pack =
Struct('L'*N).pack; values = (2**30,)*N" "pack(*values)"
--compare-to=../cpython-master/venv/bin/python
/home/sergey/tmp/cpython-master/venv/bin/python: . 10.5 us
+- 0.1 us
/home/sergey/tmp/cpython-dev/venv/bin/python: . 8.41 us +-
0.26 us
Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 10.5 us +-
0.1 us -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 8.41 us +- 0.26 us:
1.25x faster (-20%)
The mentioned pattern is also used in PyLong_AsLongLongAndOverflow(), but I
left it untouched since the proposed change doesn't seem to affect its
performance.
--
components: Interpreter Core
messages: 350091
nosy: sir-sigurd
priority: normal
severity: normal
status: open
title: speed-up PyLong_As*() for large longs
type: performance
versions: Python 3.9
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[issue37842] Initialize Py_buffer variables more efficiently
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +14975 stage: -> patch review pull_request: https://github.com/python/cpython/pull/15254 ___ Python tracker <https://bugs.python.org/issue37842> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37842] Initialize Py_buffer variables more efficiently
New submission from Sergey Fedoseev :
Argument Clinic generates `{NULL, NULL}` initializer for Py_buffer variables.
Such initializer zeroes all Py_buffer members, but as I understand only `obj`
and `buf` members are really had to be initialized. Avoiding unneeded
initialization provides tiny speed-up:
$ python -m perf timeit -s "replace = b''.replace" "replace(b'', b'')"
--compare-to=../cpython-master/venv/bin/python --duplicate=1000
/home/sergey/tmp/cpython-master/venv/bin/python: . 43.0 ns
+- 0.5 ns
/home/sergey/tmp/cpython-dev/venv/bin/python: . 41.8 ns +-
0.4 ns
Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 43.0 ns +-
0.5 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 41.8 ns +- 0.4 ns:
1.03x faster (-3%)
--
components: Argument Clinic
messages: 349582
nosy: larry, sir-sigurd
priority: normal
severity: normal
status: open
title: Initialize Py_buffer variables more efficiently
type: performance
versions: Python 3.9
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[issue37840] bytearray_getitem() handles negative index incorrectly
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +14972 stage: -> patch review pull_request: https://github.com/python/cpython/pull/15250 ___ Python tracker <https://bugs.python.org/issue37840> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37840] bytearray_getitem() handles negative index incorrectly
New submission from Sergey Fedoseev : bytearray_getitem() adjusts negative index, though that's already done by PySequence_GetItem(). This makes PySequence_GetItem(bytearray(1), -2) to return 0 instead of raise IndexError. -- components: Interpreter Core messages: 349545 nosy: sir-sigurd priority: normal severity: normal status: open title: bytearray_getitem() handles negative index incorrectly type: behavior ___ Python tracker <https://bugs.python.org/issue37840> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37837] add internal _PyLong_FromUnsignedChar() function
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +14971 stage: -> patch review pull_request: https://github.com/python/cpython/pull/15251 ___ Python tracker <https://bugs.python.org/issue37837> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37837] add internal _PyLong_FromUnsignedChar() function
New submission from Sergey Fedoseev : When compiled with default NSMALLPOSINTS, _PyLong_FromUnsignedChar() is significantly faster than other PyLong_From*(): $ python -m perf timeit -s "from collections import deque; consume = deque(maxlen=0).extend; b = bytes(2**20)" "consume(b)" --compare-to=../cpython-master/venv/bin/python /home/sergey/tmp/cpython-master/venv/bin/python: . 7.10 ms +- 0.02 ms /home/sergey/tmp/cpython-dev/venv/bin/python: . 4.29 ms +- 0.03 ms Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 7.10 ms +- 0.02 ms -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 4.29 ms +- 0.03 ms: 1.66x faster (-40%) It's mostly useful for bytes/bytearray, but also can be used in several other places. -- components: Interpreter Core messages: 349540 nosy: sir-sigurd priority: normal severity: normal status: open title: add internal _PyLong_FromUnsignedChar() function type: performance versions: Python 3.9 ___ Python tracker <https://bugs.python.org/issue37837> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37802] micro-optimization of PyLong_FromSize_t()
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +14924 stage: -> patch review pull_request: https://github.com/python/cpython/pull/15192 ___ Python tracker <https://bugs.python.org/issue37802> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue37802] micro-optimization of PyLong_FromSize_t()
New submission from Sergey Fedoseev : Currently PyLong_FromSize_t() uses PyLong_FromLong() for values < PyLong_BASE. It's suboptimal because PyLong_FromLong() needs to handle the sign. Removing PyLong_FromLong() call and handling small ints directly in PyLong_FromSize_t() makes it faster: $ python -m perf timeit -s "from itertools import repeat; _len = repeat(None, 2).__length_hint__" "_len()" --compare-to=../cpython-master/venv/bin/python --duplicate=1 /home/sergey/tmp/cpython-master/venv/bin/python: . 18.7 ns +- 0.3 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 16.7 ns +- 0.1 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 18.7 ns +- 0.3 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 16.7 ns +- 0.1 ns: 1.12x faster (-10%) $ python -m perf timeit -s "from itertools import repeat; _len = repeat(None, 2**10).__length_hint__" "_len()" --compare-to=../cpython-master/venv/bin/python --duplicate=1 /home/sergey/tmp/cpython-master/venv/bin/python: . 26.2 ns +- 0.0 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 25.0 ns +- 0.7 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 26.2 ns +- 0.0 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 25.0 ns +- 0.7 ns: 1.05x faster (-5%) $ python -m perf timeit -s "from itertools import repeat; _len = repeat(None, 2**30).__length_hint__" "_len()" --compare-to=../cpython-master/venv/bin/python --duplicate=1 /home/sergey/tmp/cpython-master/venv/bin/python: . 25.6 ns +- 0.1 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 25.6 ns +- 0.0 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 25.6 ns +- 0.1 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 25.6 ns +- 0.0 ns: 1.00x faster (-0%) This change makes PyLong_FromSize_t() consistently faster than PyLong_FromSsize_t(). So it might make sense to replace PyLong_FromSsize_t() with PyLong_FromSize_t() in __length_hint__() implementations and other similar cases. For example: $ python -m perf timeit -s "_len = iter(bytes(2)).__length_hint__" "_len()" --compare-to=../cpython-master/venv/bin/python --duplicate=1 /home/sergey/tmp/cpython-master/venv/bin/python: . 19.4 ns +- 0.3 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 17.3 ns +- 0.1 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 19.4 ns +- 0.3 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 17.3 ns +- 0.1 ns: 1.12x faster (-11%) $ python -m perf timeit -s "_len = iter(bytes(2**10)).__length_hint__" "_len()" --compare-to=../cpython-master/venv/bin/python --duplicate=1 /home/sergey/tmp/cpython-master/venv/bin/python: . 26.3 ns +- 0.1 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 25.3 ns +- 0.2 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 26.3 ns +- 0.1 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 25.3 ns +- 0.2 ns: 1.04x faster (-4%) $ python -m perf timeit -s "_len = iter(bytes(2**30)).__length_hint__" "_len()" --compare-to=../cpython-master/venv/bin/python --duplicate=1 /home/sergey/tmp/cpython-master/venv/bin/python: . 27.6 ns +- 0.1 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 26.0 ns +- 0.1 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 27.6 ns +- 0.1 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 26.0 ns +- 0.1 ns: 1.06x faster (-6%) -- components: Interpreter Core messages: 349285 nosy: sir-sigurd priority: normal severity: normal status: open title: micro-optimization of PyLong_FromSize_t() type: performance versions: Python 3.9 ___ Python tracker <https://bugs.python.org/issue37802> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue34488] improve performance of BytesIO.writelines() by avoiding creation of unused PyLongs
Sergey Fedoseev added the comment: `BytesIO.write()` and `BytesIO.writelines()` are independent of each other. -- ___ Python tracker <https://bugs.python.org/issue34488> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue31862] Port the standard library to PEP 489 multiphase initialization
Change by Sergey Fedoseev : -- pull_requests: +13420 ___ Python tracker <https://bugs.python.org/issue31862> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36030] add internal API function to create tuple without items array initialization
Change by Sergey Fedoseev : Added file: https://bugs.python.org/file48173/build_tuple_bench.py ___ Python tracker <https://bugs.python.org/issue36030> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36030] add internal API function to create tuple without items array initialization
Change by Sergey Fedoseev : Added file: https://bugs.python.org/file48174/list_as_tuple_bench.py ___ Python tracker <https://bugs.python.org/issue36030> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36030] add internal API function to create tuple without items array initialization
Sergey Fedoseev added the comment: >> This optimization also can be used for BUILD_TUPLE opcode and in pickle >> module, if it's OK to add _PyTuple_StealFromArray() function :-) > I would like to see a micro-benchmark showing that it's faster. +-+-+-+ | Benchmark | build_tuple_ref | build_tuple_untracked | +=+=+=+ | (a, ) | 19.9 ns | 19.4 ns: 1.03x faster (-3%) | +-+-+-+ | (a, 1) | 24.0 ns | 22.6 ns: 1.06x faster (-6%) | +-+-+-+ | (a, 1, 1) | 28.2 ns | 25.9 ns: 1.09x faster (-8%) | +-+-+-+ | (a, 1, 1, 1)| 31.0 ns | 29.0 ns: 1.07x faster (-6%) | +-+-+-+ | (a, 1, 1, 1, 1) | 34.7 ns | 32.2 ns: 1.08x faster (-7%) | +-+-+-+ -- ___ Python tracker <https://bugs.python.org/issue36030> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36030] add internal API function to create tuple without items array initialization
Sergey Fedoseev added the comment: > Can you please convert msg336142 into a perf script? > And then run again these benchmarks on PR 12052. ++-+--+ | Benchmark | ref | untracked| ++=+==+ | list_as_tuple(0) | 50.7 ns | 45.5 ns: 1.12x faster (-10%) | ++-+--+ | list_as_tuple(1) | 64.5 ns | 56.5 ns: 1.14x faster (-12%) | ++-+--+ | list_as_tuple(5) | 72.0 ns | 62.6 ns: 1.15x faster (-13%) | ++-+--+ | list_as_tuple(10) | 86.3 ns | 77.1 ns: 1.12x faster (-11%) | ++-+--+ | list_as_tuple(100) | 469 ns | 450 ns: 1.04x faster (-4%) | ++-+--+ -- ___ Python tracker <https://bugs.python.org/issue36030> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36030] add internal API function to create tuple without items array initialization
Sergey Fedoseev added the comment: This optimization also can be used for BUILD_TUPLE opcode and in pickle module, if it's OK to add _PyTuple_StealFromArray() function :-) -- ___ Python tracker <https://bugs.python.org/issue36030> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36030] add internal API function to create tuple without items array initialization
Sergey Fedoseev added the comment: I added WIP PR with discussed micro-optimization, here are benchmark results: $ python -m perf compare_to --min-speed 1 -G master.json tuple-untracked.json Slower (1): - sqlite_synth: 5.16 us +- 0.10 us -> 5.22 us +- 0.08 us: 1.01x slower (+1%) Faster (19): - python_startup: 12.9 ms +- 0.7 ms -> 12.2 ms +- 0.0 ms: 1.06x faster (-5%) - python_startup_no_site: 8.96 ms +- 0.29 ms -> 8.56 ms +- 0.03 ms: 1.05x faster (-4%) - raytrace: 882 ms +- 11 ms -> 854 ms +- 12 ms: 1.03x faster (-3%) - mako: 27.9 ms +- 0.8 ms -> 27.1 ms +- 0.3 ms: 1.03x faster (-3%) - scimark_monte_carlo: 176 ms +- 4 ms -> 171 ms +- 5 ms: 1.03x faster (-3%) - logging_format: 17.7 us +- 0.4 us -> 17.2 us +- 0.3 us: 1.03x faster (-3%) - telco: 11.0 ms +- 0.2 ms -> 10.8 ms +- 0.4 ms: 1.02x faster (-2%) - richards: 123 ms +- 2 ms -> 120 ms +- 2 ms: 1.02x faster (-2%) - pathlib: 35.1 ms +- 0.7 ms -> 34.6 ms +- 0.5 ms: 1.01x faster (-1%) - scimark_sparse_mat_mult: 6.97 ms +- 0.20 ms -> 6.88 ms +- 0.29 ms: 1.01x faster (-1%) - scimark_sor: 327 ms +- 6 ms -> 323 ms +- 3 ms: 1.01x faster (-1%) - scimark_fft: 570 ms +- 5 ms -> 562 ms +- 4 ms: 1.01x faster (-1%) - float: 184 ms +- 2 ms -> 182 ms +- 2 ms: 1.01x faster (-1%) - logging_simple: 15.8 us +- 0.4 us -> 15.6 us +- 0.3 us: 1.01x faster (-1%) - deltablue: 12.6 ms +- 0.2 ms -> 12.5 ms +- 0.3 ms: 1.01x faster (-1%) - crypto_pyaes: 186 ms +- 2 ms -> 184 ms +- 2 ms: 1.01x faster (-1%) - hexiom: 17.3 ms +- 0.1 ms -> 17.2 ms +- 0.1 ms: 1.01x faster (-1%) - sqlalchemy_declarative: 253 ms +- 4 ms -> 251 ms +- 3 ms: 1.01x faster (-1%) - spectral_norm: 225 ms +- 2 ms -> 223 ms +- 3 ms: 1.01x faster (-1%) -- ___ Python tracker <https://bugs.python.org/issue36030> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36030] add internal API function to create tuple without items array initialization
Change by Sergey Fedoseev : -- pull_requests: +12078 ___ Python tracker <https://bugs.python.org/issue36030> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36030] add internal API function to create tuple without items array initialization
Change by Sergey Fedoseev : -- pull_requests: +12062 ___ Python tracker <https://bugs.python.org/issue36030> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36073] sqlite crashes with converters mutating cursor
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +12008 stage: -> patch review ___ Python tracker <https://bugs.python.org/issue36073> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36073] sqlite crashes with converters mutating cursor
New submission from Sergey Fedoseev :
It's somewhat similar to bpo-10811, but for converter function:
In [197]: import sqlite3 as sqlite
...: con = sqlite.connect(':memory:', detect_types=sqlite.PARSE_COLNAMES)
...: cur = con.cursor()
...: sqlite.converters['CURSOR_INIT'] = lambda x: cur.__init__(con)
...:
...: cur.execute('create table test(x foo)')
...: cur.execute('insert into test(x) values (?)', ('foo',))
...: cur.execute('select x as "x [CURSOR_INIT]", x from test')
...:
[1]25718 segmentation fault python manage.py shell
Similar to bpo-10811, proposed patch raises ProgrammingError instead of
crashing.
--
components: Extension Modules
messages: 336283
nosy: sir-sigurd
priority: normal
severity: normal
status: open
title: sqlite crashes with converters mutating cursor
type: crash
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[issue36072] str.translate() behaves differently for ASCII-only and other strings
Change by Sergey Fedoseev : -- title: str.translate() behave differently for ASCII-only and other strings -> str.translate() behaves differently for ASCII-only and other strings ___ Python tracker <https://bugs.python.org/issue36072> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36072] str.translate() behave differently for ASCII-only and other strings
New submission from Sergey Fedoseev :
In [186]: from itertools import cycle
In [187]: class ContainerLike:
...: def __init__(self):
...: self.chars = cycle('12')
...: def __getitem__(self, key):
...: return next(self.chars)
...:
In [188]: 'aa'.translate(ContainerLike())
Out[188]: '11'
In [189]: 'ыы'.translate(ContainerLike())
Out[189]: '121212
It seems that behavior was changed in
https://github.com/python/cpython/commit/89a76abf20889551ec1ed64dee1a4161a435db5b.
At least it should be documented.
--
messages: 336279
nosy: sir-sigurd
priority: normal
severity: normal
status: open
title: str.translate() behave differently for ASCII-only and other strings
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[issue36063] replace PyTuple_SetItem() with PyTuple_SET_ITEM() in long_divmod()
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +11998 stage: -> patch review ___ Python tracker <https://bugs.python.org/issue36063> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36063] replace PyTuple_SetItem() with PyTuple_SET_ITEM() in long_divmod()
New submission from Sergey Fedoseev : This change produces minor speed-up: $ python-other -m perf timeit -s "divmod_ = divmod" "divmod_(1, 1)" --duplicate=1000 --compare-to=../cpython-master/venv/bin/python python: . 64.6 ns +- 4.8 ns python-other: . 59.4 ns +- 3.2 ns Mean +- std dev: [python] 64.6 ns +- 4.8 ns -> [python-other] 59.4 ns +- 3.2 ns: 1.09x faster (-8%) -- messages: 336194 nosy: sir-sigurd priority: normal severity: normal status: open title: replace PyTuple_SetItem() with PyTuple_SET_ITEM() in long_divmod() type: performance versions: Python 3.8 ___ Python tracker <https://bugs.python.org/issue36063> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36062] move index normalization from list_slice() to PyList_GetSlice()
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +11993 stage: -> patch review ___ Python tracker <https://bugs.python.org/issue36062> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36062] move index normalization from list_slice() to PyList_GetSlice()
New submission from Sergey Fedoseev : list_slice() is used by PyList_GetSlice(), list_subscript() and for list copying. In list_subscript() slice indices are already normalized with PySlice_AdjustIndices(), so slice normalization currently performed in list_slice() is only needed for PyList_GetSlice(). Moving this normalization from list_slice() to PyList_GetSlice() provides minor speed-up for list copying and slicing: $ python -m perf timeit -s "copy = [].copy" "copy()" --duplicate=1000 --compare-to=../cpython-master/venv/bin/python /home/sergey/tmp/cpython-master/venv/bin/python: . 26.5 ns +- 0.5 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 25.7 ns +- 0.5 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 26.5 ns +- 0.5 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 25.7 ns +- 0.5 ns: 1.03x faster (-3%) $ python -m perf timeit -s "l = [1]" "l[:]" --duplicate=1000 --compare-to=../cpython-master/venv/bin/python /home/sergey/tmp/cpython-master/venv/bin/python: . 71.5 ns +- 1.4 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 70.2 ns +- 0.9 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 71.5 ns +- 1.4 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 70.2 ns +- 0.9 ns: 1.02x faster (-2%) -- messages: 336184 nosy: sir-sigurd priority: normal severity: normal status: open title: move index normalization from list_slice() to PyList_GetSlice() type: performance versions: Python 3.8 ___ Python tracker <https://bugs.python.org/issue36062> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36030] add internal API function to create tuple without items array initialization
Sergey Fedoseev added the comment: Here's benchmarks for PyTuple_FromArray() PR: $ python -m perf timeit -s "l = [None]*0; tuple_ = tuple" "tuple_(l)" --duplicate=100 --compare-to=../cpython-master/venv/bin/python /home/sergey/tmp/cpython-master/venv/bin/python: . 50.5 ns +- 1.0 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 45.6 ns +- 1.2 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 50.5 ns +- 1.0 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 45.6 ns +- 1.2 ns: 1.11x faster (-10%) $ python -m perf timeit -s "l = [None]*1; tuple_ = tuple" "tuple_(l)" --duplicate=100 --compare-to=../cpython-master/venv/bin/python /home/sergey/tmp/cpython-master/venv/bin/python: . 61.8 ns +- 1.1 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 54.8 ns +- 0.8 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 61.8 ns +- 1.1 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 54.8 ns +- 0.8 ns: 1.13x faster (-11%) $ python -m perf timeit -s "l = [None]*5; tuple_ = tuple" "tuple_(l)" --duplicate=100 --compare-to=../cpython-master/venv/bin/python /home/sergey/tmp/cpython-master/venv/bin/python: . 68.2 ns +- 1.3 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 61.8 ns +- 1.5 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 68.2 ns +- 1.3 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 61.8 ns +- 1.5 ns: 1.10x faster (-9%) $ python -m perf timeit -s "l = [None]*10; tuple_ = tuple" "tuple_(l)" --duplicate=100 --compare-to=../cpython-master/venv/bin/python /home/sergey/tmp/cpython-master/venv/bin/python: . 88.1 ns +- 2.3 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 78.9 ns +- 3.1 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 88.1 ns +- 2.3 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 78.9 ns +- 3.1 ns: 1.12x faster (-10%) $ python -m perf timeit -s "l = [None]*100; tuple_ = tuple" "tuple_(l)" --duplicate=100 --compare-to=../cpython-master/venv/bin/python /home/sergey/tmp/cpython-master/venv/bin/python: . 477 ns +- 7 ns /home/sergey/tmp/cpython-dev/venv/bin/python: . 452 ns +- 6 ns Mean +- std dev: [/home/sergey/tmp/cpython-master/venv/bin/python] 477 ns +- 7 ns -> [/home/sergey/tmp/cpython-dev/venv/bin/python] 452 ns +- 6 ns: 1.05x faster (-5%) -- ___ Python tracker <https://bugs.python.org/issue36030> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36030] add internal API function to create tuple without items array initialization
Change by Sergey Fedoseev : -- pull_requests: +11979 ___ Python tracker <https://bugs.python.org/issue36030> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36031] add internal API function to effectively convert just created list to tuple
Sergey Fedoseev added the comment: Does this look like more real world example? Before: $ python -m perf timeit -s "t = (1, 2, 3)" "(*t, 4, 5)" . Mean +- std dev: 95.7 ns +- 2.3 ns After: $ python -m perf timeit -s "t = (1, 2, 3)" "(*t, 4, 5)" . Mean +- std dev: 85.1 ns +- 0.6 ns -- ___ Python tracker <https://bugs.python.org/issue36031> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36031] add internal API function to effectively convert just created list to tuple
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +11953 stage: -> patch review ___ Python tracker <https://bugs.python.org/issue36031> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36031] add internal API function to effectively convert just created list to tuple
New submission from Sergey Fedoseev : There are several cases in CPython sources when PyList_AsTuple() is used with just created list and immediately after that this list is Py_DECREFed. This operation can be performed more effectively since refcount of items is not changed. For example it gives such speed-up for BUILD_TUPLE_UNPACK: Before: $ python -m perf timeit -s "l = [None]*10**6" "(*l,)" . Mean +- std dev: 8.75 ms +- 0.10 ms After: $ python -m perf timeit -s "l = [None]*10**6" "(*l,)" . Mean +- std dev: 5.41 ms +- 0.07 ms -- messages: 335901 nosy: sir-sigurd priority: normal severity: normal status: open title: add internal API function to effectively convert just created list to tuple type: performance versions: Python 3.8 ___ Python tracker <https://bugs.python.org/issue36031> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36030] add internal API function to create tuple without items array initialization
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +11952 stage: -> patch review ___ Python tracker <https://bugs.python.org/issue36030> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue36030] add internal API function to create tuple without items array initialization
New submission from Sergey Fedoseev : PyTuple_New() fills items array with NULLs to make usage of Py_DECREF() safe even when array is not fully filled with real items. There are multiple cases when this initialization step can be avoided to improve performance. For example it gives such speed-up for PyList_AsTuple(): Before: $ python -m perf timeit -s "l = [None] * 10**6" "tuple(l)" . Mean +- std dev: 4.43 ms +- 0.01 ms After: $ python -m perf timeit -s "l = [None] * 10**6" "tuple(l)" . Mean +- std dev: 4.11 ms +- 0.03 ms -- messages: 335897 nosy: sir-sigurd priority: normal severity: normal status: open title: add internal API function to create tuple without items array initialization type: performance versions: Python 3.8 ___ Python tracker <https://bugs.python.org/issue36030> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue33234] Improve list() pre-sizing for inputs with known lengths
Change by Sergey Fedoseev : -- pull_requests: +10490 ___ Python tracker <https://bugs.python.org/issue33234> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue34995] functools.cached_property does not maintain the wrapped method's __isabstractmethod__
Change by Sergey Fedoseev : -- nosy: +sir-sigurd ___ Python tracker <https://bugs.python.org/issue34995> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue23460] Decimals do not obey ':g' exponential notation formatting rules
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[issue28397] Faster index range checks
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[issue34898] add mtime argument to gzip.compress
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[issue32788] Better error handling in sqlite3
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[issue21165] Optimize str.translate() for replacement with substrings and non-ASCII strings
Change by Sergey Fedoseev : -- nosy: +sir-sigurd ___ Python tracker <https://bugs.python.org/issue21165> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue34751] Hash collisions for tuples
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[issue34749] improve performance of binascii.a2b_base64()
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +8859 stage: -> patch review ___ Python tracker <https://bugs.python.org/issue34749> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue34749] improve performance of binascii.a2b_base64()
New submission from Sergey Fedoseev : I reworked implementation of binascii.a2b_base64() and there is significant speedup: $ python -m perf timeit --compare-to ~/tmp/cpython-master-venv/bin/python -s "from binascii import b2a_base64, a2b_base64; s = b2a_base64(1000 * b'b')" "a2b_base64(s)" /home/sergey/tmp/cpython-master-venv/bin/python: . 3.43 us +- 0.01 us /home/sergey/tmp/cpython-dev-venv/bin/python: . 1.52 us +- 0.01 us Mean +- std dev: [/home/sergey/tmp/cpython-master-venv/bin/python] 3.43 us +- 0.01 us -> [/home/sergey/tmp/cpython-dev-venv/bin/python] 1.52 us +- 0.01 us: 2.26x faster (-56%) $ python -m perf timeit --compare-to ~/tmp/cpython-master-venv/bin/python -s "from binascii import b2a_base64, a2b_base64; s = b2a_base64(1 * b'b')" "a2b_base64(s)" /home/sergey/tmp/cpython-master-venv/bin/python: . 76.0 ns +- 0.2 ns /home/sergey/tmp/cpython-dev-venv/bin/python: . 69.2 ns +- 0.1 ns Mean +- std dev: [/home/sergey/tmp/cpython-master-venv/bin/python] 76.0 ns +- 0.2 ns -> [/home/sergey/tmp/cpython-dev-venv/bin/python] 69.2 ns +- 0.1 ns: 1.10x faster (-9%) -- components: Extension Modules messages: 325860 nosy: sir-sigurd priority: normal severity: normal status: open title: improve performance of binascii.a2b_base64() type: performance versions: Python 3.8 ___ Python tracker <https://bugs.python.org/issue34749> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue1621] Do not assume signed integer overflow behavior
Sergey Fedoseev added the comment: > Now you rely on PyMem_Malloc() to detect the overflow. Now overflow is not possible or am I missing something? -- nosy: +sir-sigurd ___ Python tracker <https://bugs.python.org/issue1621> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue34599] improve performance of _Py_bytes_capitalize()
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +8541 stage: -> patch review ___ Python tracker <https://bugs.python.org/issue34599> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue34599] improve performance of _Py_bytes_capitalize()
New submission from Sergey Fedoseev : Currently _Py_bytes_capitalize() checks case before using conversion table, performance can be improved by using conversion table unconditionally. Benchmarks: $ python -m perf timeit --compare-to ~/tmp/cpython-master-venv/bin/python -s "b = b'0'*1000" "b.capitalize()" /home/sergey/tmp/cpython-master-venv/bin/python: . 7.26 ms +- 0.03 ms /home/sergey/tmp/cpython-dev-venv/bin/python: . 7.27 ms +- 0.04 ms Mean +- std dev: [/home/sergey/tmp/cpython-master-venv/bin/python] 7.26 ms +- 0.03 ms -> [/home/sergey/tmp/cpython-dev-venv/bin/python] 7.27 ms +- 0.04 ms: 1.00x slower (+0%) Not significant! $ python -m perf timeit --compare-to ~/tmp/cpython-master-venv/bin/python -s "b = b'a'*1000" "b.capitalize()" /home/sergey/tmp/cpython-master-venv/bin/python: . 7.25 ms +- 0.03 ms /home/sergey/tmp/cpython-dev-venv/bin/python: . 7.26 ms +- 0.03 ms Mean +- std dev: [/home/sergey/tmp/cpython-master-venv/bin/python] 7.25 ms +- 0.03 ms -> [/home/sergey/tmp/cpython-dev-venv/bin/python] 7.26 ms +- 0.03 ms: 1.00x slower (+0%) $ python -m perf timeit --compare-to ~/tmp/cpython-master-venv/bin/python -s "b = b'A'*1000" "b.capitalize()" /home/sergey/tmp/cpython-master-venv/bin/python: . 18.1 ms +- 0.0 ms /home/sergey/tmp/cpython-dev-venv/bin/python: . 7.31 ms +- 0.13 ms Mean +- std dev: [/home/sergey/tmp/cpython-master-venv/bin/python] 18.1 ms +- 0.0 ms -> [/home/sergey/tmp/cpython-dev-venv/bin/python] 7.31 ms +- 0.13 ms: 2.47x faster (-60%) -- components: Interpreter Core messages: 324707 nosy: sir-sigurd priority: normal severity: normal status: open title: improve performance of _Py_bytes_capitalize() type: performance versions: Python 3.8 ___ Python tracker <https://bugs.python.org/issue34599> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue34574] OrderedDict iterators are exhausted during pickling
Sergey Fedoseev added the comment:
Other iterators either don't support pickling or aren't mutated during pickling:
In [10]: it = iter({1})
In [11]: pickle.dumps(it)
Out[11]:
b'\x80\x04\x95\x1e\x00\x00\x00\x00\x00\x00\x00\x8c\x08builtins\x94\x8c\x04iter\x94\x93\x94]\x94K\x01a\x85\x94R\x94.'
In [12]: list(it)
Out[12]: [1]
In [13]: it = (x for x in {1})
In [14]: pickle.dumps(it)
---
TypeError Traceback (most recent call last)
in ()
> 1 pickle.dumps(it)
TypeError: can't pickle generator objects
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[issue1621] Do not assume signed integer overflow behavior
Change by Sergey Fedoseev : -- pull_requests: +8519 ___ Python tracker <https://bugs.python.org/issue1621> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue34574] OrderedDict iterators are exhausted during pickling
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +8513 stage: -> patch review ___ Python tracker <https://bugs.python.org/issue34574> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue34574] OrderedDict iterators are exhausted during pickling
New submission from Sergey Fedoseev : In [1]: from collections import OrderedDict In [2]: od = OrderedDict.fromkeys(range(10)) In [3]: it = iter(od) In [4]: it.__reduce__() Out[4]: (, ([0, 1, 2, 3, 4, 5, 6, 7, 8, 9],)) In [5]: list(it) Out[5]: [] -- messages: 324551 nosy: sir-sigurd priority: normal severity: normal status: open title: OrderedDict iterators are exhausted during pickling type: behavior ___ Python tracker <https://bugs.python.org/issue34574> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue34573] Simplify __reduce__() of set and dict iterators.
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +8512 stage: -> patch review ___ Python tracker <https://bugs.python.org/issue34573> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue34573] Simplify __reduce__() of set and dict iterators.
New submission from Sergey Fedoseev : Currently __reduce__() implementation of set and dict iterators saves items to list using next/PyList_Append(), it could be simplified by using PySequence_List(). -- components: Interpreter Core messages: 324550 nosy: sir-sigurd priority: normal severity: normal status: open title: Simplify __reduce__() of set and dict iterators. type: enhancement versions: Python 3.8 ___ Python tracker <https://bugs.python.org/issue34573> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue34488] improve performance of BytesIO.writelines() by avoiding creation of unused PyLongs
Change by Sergey Fedoseev : -- keywords: +patch pull_requests: +8374 stage: -> patch review ___ Python tracker <https://bugs.python.org/issue34488> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue34488] improve performance of BytesIO.writelines() by avoiding creation of unused PyLongs
New submission from Sergey Fedoseev : Currently BytesIO.writelines() uses BytesIO.write() which returns number of written bytes as Python ints, but these ints are not used by BytesIO.writelines(), so avoiding creation of these ints can improve performance of BytesIO.writelines() especially for a large number of small lines. Benchmarks: python -m perf timeit --compare-to ~/tmp/cpython-master-venv/bin/python -s "from io import BytesIO; lines = [b'']*1;" "BytesIO().writelines(lines)" /home/sergey/tmp/cpython-master-venv/bin/python: . 153 us +- 3 us /home/sergey/tmp/cpython-venv/bin/python: . 126 us +- 4 us Mean +- std dev: [/home/sergey/tmp/cpython-master-venv/bin/python] 153 us +- 3 us -> [/home/sergey/tmp/cpython-venv/bin/python] 126 us +- 4 us: 1.22x faster (-18%) python -m perf timeit --compare-to ~/tmp/cpython-master-venv/bin/python -s "from io import BytesIO; lines = [b'b']*1;" "BytesIO().writelines(lines)" /home/sergey/tmp/cpython-master-venv/bin/python: . 164 us +- 2 us /home/sergey/tmp/cpython-venv/bin/python: . 142 us +- 1 us Mean +- std dev: [/home/sergey/tmp/cpython-master-venv/bin/python] 164 us +- 2 us -> [/home/sergey/tmp/cpython-venv/bin/python] 142 us +- 1 us: 1.16x faster (-13%) python -m perf timeit --compare-to ~/tmp/cpython-master-venv/bin/python -s "from io import BytesIO; lines = [b'b'*10]*1;" "BytesIO().writelines(lines)" /home/sergey/tmp/cpython-master-venv/bin/python: . 387 us +- 6 us /home/sergey/tmp/cpython-venv/bin/python: . 365 us +- 8 us Mean +- std dev: [/home/sergey/tmp/cpython-master-venv/bin/python] 387 us +- 6 us -> [/home/sergey/tmp/cpython-venv/bin/python] 365 us +- 8 us: 1.06x faster (-5%) python -m perf timeit --compare-to ~/tmp/cpython-master-venv/bin/python -s "from io import BytesIO; lines = [b'b'*100]*1;" "BytesIO().writelines(lines)" /home/sergey/tmp/cpython-master-venv/bin/python: . 319 us +- 5 us /home/sergey/tmp/cpython-venv/bin/python: . 305 us +- 16 us Mean +- std dev: [/home/sergey/tmp/cpython-master-venv/bin/python] 319 us +- 5 us -> [/home/sergey/tmp/cpython-venv/bin/python] 305 us +- 16 us: 1.04x faster (-4%) python -m perf timeit --compare-to ~/tmp/cpython-master-venv/bin/python -s "from io import BytesIO; lines = [b'b'*1000]*1;" "BytesIO().writelines(lines)" /home/sergey/tmp/cpython-master-venv/bin/python: . 1.13 ms +- 0.02 ms /home/sergey/tmp/cpython-venv/bin/python: . 988 us +- 88 us Mean +- std dev: [/home/sergey/tmp/cpython-master-venv/bin/python] 1.13 ms +- 0.02 ms -> [/home/sergey/tmp/cpython-venv/bin/python] 988 us +- 88 us: 1.14x faster (-12%) python -m perf timeit --compare-to ~/tmp/cpython-master-venv/bin/python -s "from io import BytesIO; lines = [b'b'*1]*1;" "BytesIO().writelines(lines)" /home/sergey/tmp/cpython-master-venv/bin/python: . 38.7 ms +- 0.1 ms /home/sergey/tmp/cpython-venv/bin/python: . 38.2 ms +- 0.1 ms Mean +- std dev: [/home/sergey/tmp/cpython-master-venv/bin/python] 38.7 ms +- 0.1 ms -> [/home/sergey/tmp/cpython-venv/bin/python] 38.2 ms +- 0.1 ms: 1.01x faster (-1%) -- components: Extension Modules messages: 324011 nosy: sir-sigurd priority: normal severity: normal status: open title: improve performance of BytesIO.writelines() by avoiding creation of unused PyLongs type: performance versions: Python 3.8 ___ Python tracker <https://bugs.python.org/issue34488> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue34395] memory leaks in error handling in csv and pickle modules
Change by Sergey Fedoseev : -- pull_requests: +8262 ___ Python tracker <https://bugs.python.org/issue34395> ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
