From: ivonastojanovic <80911834+ivonastojanovic@users.noreply.github.com>
Date: Tue, 28 Apr 2026 16:42:21 +0000 (+0100)
Subject: gh-142927: Fix inverted flamegraph width (#148568)
X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=993e204ad44fd95ac522a7903f83a4bbe5d3af9c;p=thirdparty%2FPython%2Fcpython.git

gh-142927: Fix inverted flamegraph width (#148568)

Fix inverted flamegraph width

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.
---

diff --git a/Lib/profiling/sampling/_flamegraph_assets/flamegraph.js b/Lib/profiling/sampling/_flamegraph_assets/flamegraph.js
index d7a8890d4a1a..3f884c4c690f 100644
--- a/Lib/profiling/sampling/_flamegraph_assets/flamegraph.js
+++ b/Lib/profiling/sampling/_flamegraph_assets/flamegraph.js
@@ -1063,11 +1063,7 @@ function populateStats(data) {
     funcname = funcname || 'unknown';
 
     if (filename !== 'unknown' && funcname !== 'unknown' && node.value > 0) {
-      let childrenValue = 0;
-      if (node.children) {
-        childrenValue = node.children.reduce((sum, child) => sum + child.value, 0);
-      }
-      const directSamples = Math.max(0, node.value - childrenValue);
+      const directSamples = node.self || 0;
 
       const funcKey = `${filename}:${node.lineno || '?'}:${funcname}`;
 
@@ -1345,14 +1341,13 @@ function processLeaf(invertedRoot, path, leafNode, isDifferential) {
 }
 
 function traverseInvert(path, currentNode, invertedRoot, isDifferential) {
-  const children = currentNode.children || [];
-  const childThreads = new Set(children.flatMap(c => c.threads || []));
-  const selfThreads = (currentNode.threads || []).filter(t => !childThreads.has(t));
+  const selfValue = currentNode.self || 0;
 
-  if (selfThreads.length > 0) {
-    processLeaf(invertedRoot, path, { ...currentNode, threads: selfThreads }, isDifferential);
+  if (selfValue > 0) {
+    processLeaf(invertedRoot, path, { ...currentNode, value: selfValue }, isDifferential);
   }
 
+  const children = currentNode.children || [];
   children.forEach(child => traverseInvert(path.concat([child]), child, invertedRoot, isDifferential));
 }