用 Python 3.15 对 web-edit 做性能分析：火焰图与源码热力图

Profiling web-edit with Python 3.15: flame graphs and source heatmaps

AI 导读

用 Python 3.15 内置的 `profiling.sampling` 对未修改的 web-edit 应用做采样分析，发现混合换行符保留是编辑负载的主要瓶颈：`preserve_endings` 出现在 64.8% 的 15,296 个 CPU 栈中，`SequenceMatcher.find_longest_match` 占叶子样本的 38.3%。

正文

Research Profiling web-edit with Python 3.15: flame graphs and source heatmaps — Profiling the unmodified web-edit app with Python 3.15’s built-in `profiling.sampling` revealed that mixed line-ending preservation dominated a busy editing workload: `preserve_endings` appeared in 64.8% of 15,296 recorded CPU stacks, with `SequenceMatcher.find_longest_match` contributing 38.3% of leaf samples. Sampling all threads was essential, since 95.1% of stacks came from AnyIO’s worker thread and would have been missed by a main-thread-only profile.

I put the new Python 3.15 profiler through its paces by having GPT-6 Astra Extra High in Codex run it against my new web-edit app:

I need a Python 3.15 flame graph and heatmap demo of the "web-edit" app from PyPI - research first then make me those demos

Here's the resulting example flame graph and heatmap.

来源：Simon Willison · simonwillison.net