Search results

Avoid boolean objects when branching in the JIT

interpreter-core(Objects, Python, Grammar, and Parser dirs)(Objects, Python, Grammar, and Parser dirs)

performancePerformance or resource usagePerformance or resource usage

topic-JIT

Status: Open.

#149238 In python/cpython;

· markshannon opened on May 1, 2026

Avoid adding dependencies on immutable, immortal classes in the JIT

interpreter-core(Objects, Python, Grammar, and Parser dirs)(Objects, Python, Grammar, and Parser dirs)

performancePerformance or resource usagePerformance or resource usage

topic-JIT

Status: Open.

#149217 In python/cpython;

· markshannon opened on May 1, 2026

unpack_sequence benchmark runs slower under JIT

performancePerformance or resource usagePerformance or resource usage

topic-JIT

type-bugAn unexpected behavior, bug, or errorAn unexpected behavior, bug, or error

Status: Open.

#149212 In python/cpython;

· eendebakpt opened on May 1, 2026

Avoid double checking tp_as_number, tp_as_sequence and tp_as_mapping

interpreter-core(Objects, Python, Grammar, and Parser dirs)(Objects, Python, Grammar, and Parser dirs)

performancePerformance or resource usagePerformance or resource usage

type-featureA feature request or enhancementA feature request or enhancement

Status: Open.

#149180 In python/cpython;

· markshannon opened on Apr 30, 2026

Reduce size (by half or more) of debug JIT stencils.

3.15new features, bugs and security fixesnew features, bugs and security fixes

interpreter-core(Objects, Python, Grammar, and Parser dirs)(Objects, Python, Grammar, and Parser dirs)

performancePerformance or resource usagePerformance or resource usage

topic-JIT

Status: Open.

#148960 In python/cpython;

· markshannon opened on Apr 24, 2026

GC in 3.14t can defer too much, resulting in high memory use

interpreter-core(Objects, Python, Grammar, and Parser dirs)(Objects, Python, Grammar, and Parser dirs)

performancePerformance or resource usagePerformance or resource usage

topic-free-threading

type-bugAn unexpected behavior, bug, or errorAn unexpected behavior, bug, or error

Status: Open.

#148937 In python/cpython;

· nascheme opened on Apr 23, 2026

Speed up parser by caching normalized identifiers?

interpreter-core(Objects, Python, Grammar, and Parser dirs)(Objects, Python, Grammar, and Parser dirs)

performancePerformance or resource usagePerformance or resource usage

topic-parser

type-featureA feature request or enhancementA feature request or enhancement

Status: Open.

#148931 In python/cpython;

· StanFromIreland opened on Apr 23, 2026

poor scaling of descriptors in free-threading

interpreter-core(Objects, Python, Grammar, and Parser dirs)(Objects, Python, Grammar, and Parser dirs)

performancePerformance or resource usagePerformance or resource usage

topic-free-threading

type-bugAn unexpected behavior, bug, or errorAn unexpected behavior, bug, or error

Status: Open.

#148906 In python/cpython;

· kumaraditya303 opened on Apr 23, 2026

Extend and improve LOAD_COMMON_CONSTANT

interpreter-core(Objects, Python, Grammar, and Parser dirs)(Objects, Python, Grammar, and Parser dirs)

performancePerformance or resource usagePerformance or resource usage

type-featureA feature request or enhancementA feature request or enhancement

Status: Open.

#148871 In python/cpython;

· markshannon opened on Apr 22, 2026

sets with >30 elements not constant-folded in in/not in and for loops

3.14bugs and security fixesbugs and security fixes

3.15new features, bugs and security fixesnew features, bugs and security fixes

interpreter-core(Objects, Python, Grammar, and Parser dirs)(Objects, Python, Grammar, and Parser dirs)

performancePerformance or resource usagePerformance or resource usage

type-bugAn unexpected behavior, bug, or errorAn unexpected behavior, bug, or error

Status: Open.

#148817 In python/cpython;

· itamaro opened on Apr 21, 2026

Speed up multiline regexes anchored by ^.

extension-modulesC modules in the Modules dirC modules in the Modules dir

performancePerformance or resource usagePerformance or resource usage

topic-regex

type-featureA feature request or enhancementA feature request or enhancement

Status: Open.

#148762 In python/cpython;

· haampie opened on Apr 19, 2026

Use memchr in SRE's prefix scanner

extension-modulesC modules in the Modules dirC modules in the Modules dir

performancePerformance or resource usagePerformance or resource usage

topic-regex

type-featureA feature request or enhancementA feature request or enhancement

Status: Open.

#148729 In python/cpython;

· haampie opened on Apr 18, 2026