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 d7a8890d4a1ad95e21e95f2cc91223ee75996696..3f884c4c690fd1f543ac81fcc13b9839b8bca879 100644 (file)
--- 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));
 }