gh-142927: Fix inverted flamegraph width#148568
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pablogsal merged 1 commit intoApr 28, 2026
python:mainpython/cpython:mainfrom
ivonastojanovic:inverted_flamegraph_widthivonastojanovic/cpython:inverted_flamegraph_widthCopy head branch name to clipboard
Merged
gh-142927: Fix inverted flamegraph width#148568pablogsal merged 1 commit intopython:mainpython/cpython:mainfrom ivonastojanovic:inverted_flamegraph_widthivonastojanovic/cpython:inverted_flamegraph_widthCopy head branch name to clipboard
pablogsal merged 1 commit into
python:mainpython/cpython:mainfrom
ivonastojanovic:inverted_flamegraph_widthivonastojanovic/cpython:inverted_flamegraph_widthCopy head branch name to clipboard
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The inverted view used thread presence as a proxy for self time. This missed self samples on C-level wrapper frames like _run_code, where the node's thread always appears in its children too. Those samples were silently dropped, causing the chart to render narrower than full width. Now uses the explicit self field on each node instead of the thread heuristic.
pablogsal
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Apr 28, 2026
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The inverted view used thread presence as a proxy for self time. This missed self samples on C-level wrapper frames like
_run_code, where the node's thread always appears in its children too. Those samples were silently dropped, causing the chart to render narrower than full width. Now uses the explicit self field on each node instead of the thread heuristic.CC: @pablogsal @lkollar
The issue: