python/cpython issues and pull requests

#138537 - gh-138535: Optimize fill_time for typical timestamps

Pull Request - State: closed - Opened by jbosboom 7 months ago - 6 comments
Labels: performance, awaiting review

#138535 - Optimize posixmodule.c:fill_time for typical timestamps

Issue - State: closed - Opened by jbosboom 7 months ago
Labels: type-feature, performance, extension-modules

#138429 - gh-132657: Make deepcopy and copy scale with free-threading

Pull Request - State: closed - Opened by eendebakpt 7 months ago
Labels: performance, awaiting merge, stdlib, topic-free-threading

#138050 - Streamline the `MAKE_WARM` micro-op

Issue - State: open - Opened by markshannon 7 months ago
Labels: performance, interpreter-core, topic-JIT, 3.15

#137403 - Use parallel LTO compilation with gcc

Issue - State: closed - Opened by tacaswell 8 months ago - 7 comments
Labels: type-feature, performance, build

#137138 - Performance regression: typing.cast() with Union types causes 15-60x slowdown in hot code paths

Issue - State: closed - Opened by hyfjjjj 8 months ago - 4 comments
Labels: type-bug, performance, interpreter-core, topic-typing, pending

#137121 - Calls to `memcpy` are slow for `2^k+1` elements (AMD-specific)

Issue - State: closed - Opened by bjorn-martinsson 8 months ago - 48 comments
Labels: type-bug, performance, interpreter-core, pending

#137095 - Optimize heapq.nlargest/nsmallest by switching to sorting when k is large relative to n

Issue - State: closed - Opened by MengAiDev 8 months ago - 3 comments
Labels: type-feature, performance, stdlib, extension-modules, pending

#136669 - build `_asyncio` module as static module

Issue - State: closed - Opened by kumaraditya303 8 months ago - 1 comment
Labels: performance, extension-modules, build

#136599 - Improve long_hash

Issue - State: closed - Opened by eendebakpt 8 months ago - 1 comment
Labels: type-feature, performance, interpreter-core

#136528 - GH-135904: Improve the JIT's performance on macOS

Pull Request - State: closed - Opened by brandtbucher 9 months ago - 1 comment
Labels: performance, awaiting merge, skip news, interpreter-core, topic-JIT

#136107 - gh-132657: Avoid locks and refcounts in frozenset operations

Pull Request - State: open - Opened by eendebakpt 9 months ago - 2 comments
Labels: performance, awaiting review

#136107 - gh-132657: Avoid locks and refcounts in frozenset operations

Pull Request - State: closed - Opened by eendebakpt 9 months ago - 3 comments
Labels: performance, awaiting merge

#135952 - Support chunk sending in `smtplib`

Issue - State: open - Opened by jsbucy 9 months ago - 5 comments
Labels: type-feature, performance, stdlib, topic-email

#135905 - GH-135904: Optimize the JIT's assembly control flow

Pull Request - State: open - Opened by brandtbucher 9 months ago
Labels: performance, interpreter-core, topic-JIT

#135905 - GH-135904: Optimize the JIT's assembly control flow

Pull Request - State: open - Opened by brandtbucher 9 months ago - 1 comment
Labels: performance, awaiting merge, interpreter-core, topic-JIT

#135904 - JIT Assembly Optimization

Issue - State: open - Opened by brandtbucher 9 months ago
Labels: performance, interpreter-core, topic-JIT, 3.15

#135824 - `min(<range>)` and `max(<range>)` can cause indefinite, uninterruptable interpreter hangs

Issue - State: closed - Opened by finite-state-machine 9 months ago - 5 comments
Labels: type-feature, performance, interpreter-core

#135779 - GH-90117: Check for `list` and `tuple` before `MappingView` in `pprint`

Pull Request - State: open - Opened by brandtbucher 9 months ago
Labels: performance, awaiting merge, stdlib

#135779 - GH-90117: Check for `list` and `tuple` before `MappingView` in `pprint`

Pull Request - State: closed - Opened by brandtbucher 9 months ago
Labels: performance, awaiting merge, stdlib

#135575 - `MutableMapping.update` performance improvement

Issue - State: closed - Opened by randolf-scholz 9 months ago - 1 comment
Labels: type-feature, performance

#135480 - Flatten itertools.chain objects?

Issue - State: closed - Opened by tim-one 9 months ago - 4 comments
Labels: type-feature, performance, extension-modules

#135336 - Add fast path to json string encoding

Issue - State: open - Opened by nineteendo 10 months ago
Labels: type-feature, performance, extension-modules

#135239 - Smarter use of a mutex in incremental HMAC and hash functions

Issue - State: open - Opened by picnixz 10 months ago - 1 comment
Labels: type-feature, performance, extension-modules

#135043 - Speed sorting tuples whose first elements have the same type

Issue - State: closed - Opened by tim-one 10 months ago - 4 comments
Labels: type-feature, performance

#134821 - Automatically defer heavily shared objects in free-threading.

Issue - State: open - Opened by Fidget-Spinner 10 months ago
Labels: type-feature, performance, topic-free-threading

#134728 - _TIER2_RESUME_CHECK is costly in the JIT

Issue - State: closed - Opened by Fidget-Spinner 10 months ago - 6 comments
Labels: type-feature, performance, interpreter-core, topic-JIT

#134689 - Add Non-Refcounted Operations for common types using _PyStackRef

Issue - State: open - Opened by Fidget-Spinner 10 months ago
Labels: type-feature, performance, interpreter-core, topic-free-threading, topic-JIT

#134584 - Eliminate redundant refcounting in the JIT

Issue - State: open - Opened by Fidget-Spinner 10 months ago
Labels: type-feature, performance, interpreter-core, topic-JIT

#134403 - GH-131798: Optimize cached class attributes and methods in the JIT

Pull Request - State: open - Opened by brandtbucher 10 months ago
Labels: performance, sprint, awaiting core review, interpreter-core, topic-JIT

#134373 - GH-131798: Narrow types more aggressively in the JIT

Pull Request - State: closed - Opened by brandtbucher 10 months ago
Labels: performance, awaiting core review, interpreter-core, topic-JIT

#134173 - concurrent.futures→asyncio state transfer is a bottleneck

Issue - State: closed - Opened by bdraco 10 months ago - 1 comment
Labels: performance, topic-asyncio, stdlib

#134140 - Add replication to LOAD_FAST_BORROW to speed up the JIT

Issue - State: closed - Opened by Fidget-Spinner 10 months ago - 1 comment
Labels: type-feature, performance, sprint, topic-JIT

#133669 - gh-132380: Use unicode hash/compare for the mcache.

Pull Request - State: open - Opened by nascheme 11 months ago - 5 comments
Labels: performance, awaiting core review, topic-free-threading

#133669 - gh-132380: Use unicode hash/compare for the mcache.

Pull Request - State: open - Opened by nascheme 11 months ago
Labels: performance, topic-free-threading

#133544 - gh-132917: Use /proc/self/status for mem usage info.

Pull Request - State: closed - Opened by nascheme 11 months ago - 4 comments
Labels: performance, awaiting merge, skip news, topic-free-threading

#133544 - gh-132917: Use /proc/self/status for mem usage info.

Pull Request - State: closed - Opened by nascheme 11 months ago - 6 comments
Labels: performance, skip news, topic-free-threading

#133399 - gh-132917: Check resident set size (RSS) before GC trigger.

Pull Request - State: closed - Opened by nascheme 11 months ago - 2 comments
Labels: performance, awaiting merge, topic-free-threading

#133186 - json: Optimize escaping string in Encoder

Pull Request - State: open - Opened by methane 11 months ago
Labels: performance, skip issue, extension-modules

#133186 - json: Optimize escaping string in Encoder

Pull Request - State: open - Opened by methane 11 months ago - 15 comments
Labels: performance, skip issue, awaiting core review, extension-modules

#133171 - Make the JIT thread-safe

Issue - State: open - Opened by brandtbucher 11 months ago
Labels: performance, interpreter-core, topic-JIT

#133160 - gh-133059: Increase _PY_NSMALLPOSINTS size

Pull Request - State: closed - Opened by dg-pb 11 months ago - 3 comments
Labels: performance, awaiting merge

#133059 - Increase _PY_NSMALLPOSINTS size

Issue - State: closed - Opened by dg-pb 11 months ago - 5 comments
Labels: type-feature, performance, interpreter-core

#132952 - #127648 introduced a ~12% performance regression in `python_startup_no_site` benchmark

Issue - State: closed - Opened by mdboom 11 months ago - 8 comments
Labels: type-bug, performance, interpreter-core

#132917 - 15x Performance regression with shared list appends in free-threaded mode

Issue - State: open - Opened by gptsarthak 11 months ago - 9 comments
Labels: performance, interpreter-core, pending, topic-free-threading

#132893 - Improve accuracy of NormalDist.cdf

Issue - State: closed - Opened by rhettinger 11 months ago - 1 comment
Labels: performance, 3.14

#132652 - GH-132380: Add optimization for non-interned type lookup.

Pull Request - State: closed - Opened by nascheme 11 months ago - 1 comment
Labels: performance, awaiting core review, topic-free-threading

#132651 - [3.13] GH-132380: Add optimization for non-interned type lookup.

Pull Request - State: closed - Opened by nascheme 11 months ago - 1 comment
Labels: performance, awaiting core review, 3.13, topic-free-threading

#132566 - `pathlib.Path.move()` consumes too much disk space

Issue - State: open - Opened by barneygale 11 months ago
Labels: type-bug, performance, topic-pathlib

#132472 - Speed up `Fraction.round` for large negative `ndigits`

Issue - State: closed - Opened by devdanzin 11 months ago - 7 comments
Labels: type-feature, performance, stdlib

#132424 - gh-132336: Only mark slow path functions used by the interpreter loop as noinline in free-threaded builds

Pull Request - State: open - Opened by mpage 12 months ago
Labels: performance, awaiting core review, skip news, interpreter-core, topic-free-threading

#132381 - [3.13] GH-132380: Avoid locking in _PyType_LookupRef()

Pull Request - State: closed - Opened by nascheme 12 months ago - 4 comments
Labels: performance, 3.13, topic-free-threading

#132381 - [3.13] GH-132380: Avoid locking in _PyType_LookupRef()

Pull Request - State: open - Opened by nascheme 12 months ago - 3 comments
Labels: performance, 3.13, topic-free-threading

#132380 - Lock contention inside `_PyType_LookupRef`

Issue - State: open - Opened by nascheme 12 months ago
Labels: type-feature, performance, topic-free-threading

#132372 - Improve performance in DictConfigurator by optimizing logger lookup

Issue - State: open - Opened by allrob23 12 months ago - 5 comments
Labels: type-feature, performance, stdlib

#132320 - random._randbelow soft fix with performance gain

Issue - State: closed - Opened by dg-pb 12 months ago - 2 comments
Labels: type-bug, performance, stdlib

#132310 - `from ... import ...` has a significant performance overhead

Issue - State: closed - Opened by Dreamsorcerer 12 months ago - 4 comments
Labels: type-bug, performance, pending

#132290 - GH-132657: Add lock-free set contains implementation

Pull Request - State: open - Opened by nascheme 12 months ago - 1 comment
Labels: performance, topic-free-threading

#132289 - GH-131798: Remove JIT guards for `dict`, `frozenset`, `list`, `set`, and `tuple`

Pull Request - State: closed - Opened by brandtbucher 12 months ago - 3 comments
Labels: performance, awaiting merge, interpreter-core, topic-JIT

#132278 - GH-131798: Skip `self`/`NULL` checks for some known non-methods

Pull Request - State: closed - Opened by brandtbucher 12 months ago - 5 comments
Labels: performance, awaiting core review, interpreter-core

#132185 - test_expanduser_pwd2 in test_posixpath can be very slow

Issue - State: closed - Opened by itamaro 12 months ago - 5 comments
Labels: type-bug, performance, tests

#132166 - Add checking if both strings are the same in `SequenceMatcher.find_longest_match`

Issue - State: open - Opened by jurgenwigg 12 months ago - 10 comments
Labels: type-feature, performance, stdlib

#132153 - gh-131798: JIT: Narrow the return type of `_BINARY_OP_SUBSCR_STR_INT` to `str`

Pull Request - State: open - Opened by tomasr8 12 months ago - 3 comments
Labels: performance, awaiting merge, interpreter-core, topic-JIT

#132153 - gh-131798: JIT: Narrow the return type of `_BINARY_OP_SUBSCR_STR_INT` to `str`

Pull Request - State: closed - Opened by tomasr8 12 months ago - 4 comments
Labels: performance, awaiting merge, interpreter-core, topic-JIT

#132103 - GH-118761: Expose more core interpreter types in ``_types``

Pull Request - State: closed - Opened by AA-Turner 12 months ago - 6 comments
Labels: performance, awaiting merge, skip news

#132042 - Optimize class creation

Issue - State: open - Opened by JelleZijlstra 12 months ago
Labels: performance, interpreter-core

#132037 - gh-118761: Optimise import time for ``string``

Pull Request - State: open - Opened by AA-Turner 12 months ago - 2 comments
Labels: performance, awaiting core review

#132036 - gh-118761: Optimise import time for ``shlex``

Pull Request - State: open - Opened by AA-Turner 12 months ago - 3 comments
Labels: performance, awaiting core review

#132036 - gh-118761: Optimise import time for ``shlex``

Pull Request - State: open - Opened by AA-Turner 12 months ago
Labels: performance

#132031 - gh-118761: Use `enum._simple_enum` for `annotationlib.Format`

Pull Request - State: open - Opened by AA-Turner 12 months ago - 2 comments
Labels: performance, awaiting core review, skip news

#131988 - Multithreaded scaling regression in 3.13.1t

Issue - State: closed - Opened by colesbury 12 months ago - 2 comments
Labels: type-bug, performance, interpreter-core, release-blocker, 3.13, topic-free-threading

#131959 - Generator vs List comprehension optimzations

Issue - State: closed - Opened by Marius-Juston 12 months ago - 3 comments
Labels: type-feature, performance, interpreter-core, pending

#131955 - Allow to disable internal string key caching for `json.loads()`

Issue - State: closed - Opened by nineteendo 12 months ago - 21 comments
Labels: type-feature, performance, stdlib

#131953 - gh-118761: Optimise import time for ast

Pull Request - State: closed - Opened by AA-Turner 12 months ago - 11 comments
Labels: performance

#131800 - GH-131798: Allow the JIT to remove more `int`/`float`/`str` guards

Pull Request - State: closed - Opened by brandtbucher 12 months ago - 2 comments
Labels: performance, awaiting core review, interpreter-core, topic-JIT

#131798 - Better uop coverage in the JIT optimizer

Issue - State: open - Opened by brandtbucher 12 months ago
Labels: performance, interpreter-core, 3.14, topic-JIT

#131791 - Add `only_whitespace` option to `textwrap.dedent`

Issue - State: closed - Opened by Marius-Juston 12 months ago - 19 comments
Labels: type-feature, performance, stdlib

#131750 - GH-119866: Don't clear `frame->stackpointer` on release builds

Pull Request - State: open - Opened by brandtbucher 12 months ago
Labels: performance, awaiting core review, skip news, interpreter-core

#131750 - GH-119866: Don't clear `frame->stackpointer` on release builds

Pull Request - State: open - Opened by brandtbucher 12 months ago
Labels: performance, skip news, interpreter-core

#131738 - optimize any/all/tuple calls with a generator expression arg

Issue - State: closed - Opened by iritkatriel 12 months ago
Labels: type-feature, performance, interpreter-core

#131525 - Caching the tuple hash calculation speeds up some code significantly

Issue - State: closed - Opened by mdboom about 1 year ago - 2 comments
Labels: type-feature, performance, interpreter-core

#131435 - random.randint performance improvement

Issue - State: closed - Opened by dg-pb about 1 year ago - 1 comment
Labels: type-feature, performance, stdlib

#131278 - Support building using "computed gotos" for clang-cl on Windows

Issue - State: closed - Opened by chris-eibl about 1 year ago
Labels: type-feature, performance, OS-windows, build

#131269 - Avoid binding functions to temporaries in `random.py`

Issue - State: closed - Opened by colesbury about 1 year ago - 1 comment
Labels: type-feature, performance, stdlib

#131262 - Use Windows `IFileOperation` to implement copying/moving/deleting in pathlib

Issue - State: open - Opened by barneygale about 1 year ago
Labels: type-feature, performance, OS-windows, topic-pathlib

#131196 - Improve perfomance of UUID.hex and UUID.str by using bytes.hex()

Issue - State: closed - Opened by booqoffsky about 1 year ago - 4 comments
Labels: type-feature, performance, stdlib

#131194 - Dictionary max modifications threshold too low for JIT

Issue - State: open - Opened by Fidget-Spinner about 1 year ago - 3 comments
Labels: performance, interpreter-core, topic-JIT

#131038 - 3.13: `test_perf_profiler` fails on aarch64 Fedora Stable Refleaks buildbot

Issue - State: open - Opened by encukou about 1 year ago - 12 comments
Labels: type-bug, performance, 3.13

#131035 - use -flto=thin for clang-cl on Windows

Issue - State: closed - Opened by chris-eibl about 1 year ago - 2 comments
Labels: type-feature, performance, OS-windows, build

#130887 - JIT: remove jumps at the end of every micro op on aarch64

Issue - State: closed - Opened by diegorusso about 1 year ago
Labels: performance, interpreter-core, triaged, 3.14, topic-JIT

#130706 - Move reftracer call from `_Py_Dealloc` to non-inlined function call

Issue - State: open - Opened by colesbury about 1 year ago
Labels: performance, topic-free-threading

#130704 - Optimize reference counting overhead of `LOAD_FAST` variants

Issue - State: closed - Opened by mpage about 1 year ago
Labels: type-feature, performance, interpreter-core

#130659 - GH-130415: Use boolean guards to narrow types to values in the JIT

Pull Request - State: closed - Opened by brandtbucher about 1 year ago - 5 comments
Labels: performance, awaiting core review, interpreter-core, topic-JIT

#130477 - GH-130415: Optimize JIT path for _TO_BOOL_INT branching

Pull Request - State: closed - Opened by Klaus117 about 1 year ago - 5 comments
Labels: performance, awaiting merge, interpreter-core, topic-JIT

#130476 - GH-130415: Narrow `str` to `""` based on boolean tests

Pull Request - State: open - Opened by fluhus about 1 year ago - 5 comments
Labels: performance, awaiting merge, interpreter-core, topic-JIT

#130476 - GH-130415: Narrow `str` to `""` based on boolean tests

Pull Request - State: closed - Opened by fluhus about 1 year ago - 5 comments
Labels: performance, awaiting merge, interpreter-core, topic-JIT

#130415 - Better constant narrowing in the JIT optimizer

Issue - State: open - Opened by brandtbucher about 1 year ago
Labels: performance, interpreter-core, 3.14, topic-JIT

#130097 - GH-115802: JIT using the "medium" code model on `x86_64-unknown-linux-gnu`

Pull Request - State: open - Opened by brandtbucher about 1 year ago
Labels: performance, interpreter-core, topic-JIT

#129987 - computed-goto interpreter: Prevent the compiler from merging `DISPATCH` calls

Issue - State: closed - Opened by nelhage about 1 year ago - 28 comments
Labels: type-feature, performance, interpreter-core

#129716 - GH-129715: Remove `_DYNAMIC_EXIT`

Pull Request - State: closed - Opened by brandtbucher about 1 year ago
Labels: performance, awaiting merge, interpreter-core, topic-JIT

GitHub / python/cpython issues and pull requests