python-performance-optimization

A guide to measuring and improving the speed and memory use of Python programs. Profiling means collecting information about which parts of a program consume the most time or memory.

In plain words
What is it for?
Use it to investigate slow code, reduce memory consumption, find leaks, optimize data processing or database access, and evaluate performance improvements.
Why use it?
It helps identify the actual bottleneck before changing code, instead of relying on guesses. It covers CPU work, memory use, database queries, input/output, and production behavior.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/julien777z/agent-sync-action/python-performance-optimization
Any agent
npx skills add julien777z/agent-sync-action --skill python-performance-optimization
Clone the repo
git clone --depth 1 https://github.com/julien777z/agent-sync-action

Made for: Claude Code, Codex.

Per session 40 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 720 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 88% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00040 $0.00720
Opus 5 $0.00020 $0.00360
Sonnet 5 $0.00008 $0.00144
Haiku 4.5 $0.00004 $0.00072

Measured yesterday against content hash 9276caab8766, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

python-performance-optimization scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

88% identical to python-performance-optimization — 2 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.agents/skills/python-performance-optimization/SKILL.md · 103 lines

How it starts

The opening of the file, as written. The whole thing — 103 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Python Performance Optimization

Comprehensive guide to profiling, analyzing, and optimizing Python code for better performance, including CPU profiling, memory optimization, and implementation best practices.

When to Use This Skill

  • Identifying performance bottlenecks in Python applications
  • Reducing application latency and response times
  • Optimizing CPU-intensive operations
  • Reducing memory consumption and memory leaks
  • Improving database query performance
  • Optimizing I/O operations
  • Speeding up data processing pipelines
  • Implementing high-performance algorithms
  • Profiling production applications

Core Concepts

1. Profiling Types

  • CPU Profiling: Identify time-consuming functions
  • Memory Profiling: Track memory allocation and leaks
  • Line Profiling: Profile at line-by-line granularity
  • Call Graph: Visualize function call relationships

2. Performance Metrics

  • Execution Time: How long operations take
  • Memory Usage: Peak and average memory consumption
  • CPU Utilization: Processor usage patterns
  • I/O Wait: Time spent on I/O operations

3. Optimization Strategies

  • Algorithmic: Better algorithms and data structures
  • Implementation: More efficient code patterns
  • Parallelization: Multi-threading/processing
  • Caching: Avoid redundant computation
  • Native Extensions: C/Rust for critical paths

Quick Start

Basic Timing

import time

def measure_time():
    """Simple timing measurement."""
    start = time.time()

    # Your code here
    result = sum(range(1000000))

    elapsed = time.time() - start
    print(f"Execution time: {elapsed:.4f} seconds")
    return result

# Better: use timeit for accurate measurements
import timeit

execution_time = timeit.timeit(
    "sum(range(1000000))",
    number=100
)
print(f"Average time: {execution_time/100:.6f} seconds")

Detailed patterns and worked examples

Detailed pattern documentation lives in references/details.md. Read that file when the navigation tier above is insufficient.

Read the full file on GitHub · 103 lines

Files

What ships with it

3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 103 lines · 40 tokens per session scan A 9276caab8766

Subscribe to this mod's changes

python-performance-optimization is a skill published in the GitHub repository julien777z/agent-sync-action (5 stars, last pushed 2d ago), licensed MIT. It adds 40 tokens to every session and 720 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 88% identical to python-performance-optimization, differing in 2 lines, and is treated as a copy.

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