Reduce ExtractWorkflowNameFromFile overhead in the title-scan path#31598
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pelikhan merged 5 commits intoMay 12, 2026
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[WIP] Fix performance regression in ExtractWorkflowNameFromFile
Reduce May 11, 2026
ExtractWorkflowNameFromFile overhead in the title-scan path
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Pull request overview
Reduces allocation overhead in the hot path used to extract workflow titles from file content by reusing the initial bufio.Scanner buffer, while preserving behavior for large frontmatter lines.
Changes:
- Introduces a small
sync.Pool-backed reusable scanner buffer forfastParseTitleFromReader(keeping the 1 MB max token size). - Adds a regression test ensuring H1 extraction still works when frontmatter contains a line larger than the default scanner token size.
- Minor gofmt-driven alignment update in a frontmatter extraction test case.
Show a summary per file
| File | Description |
|---|---|
| pkg/cli/workflows.go | Adds pooled scanner buffer reuse in fastParseTitleFromReader to reduce per-call allocations. |
| pkg/cli/commands_utils_test.go | Adds regression coverage for title extraction with oversized frontmatter lines. |
| pkg/parser/frontmatter_extraction_test.go | Formatting/alignment update in an existing test table entry. |
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- Files reviewed: 2/3 changed files
- Comments generated: 2
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| var workflowTitleScannerBufferPool = sync.Pool{ | ||
| New: func() any { | ||
| return make([]byte, 4*1024) |
Comment on lines
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| filePath := filepath.Join(tmpDir, "large-frontmatter.md") | ||
| content := "---\nblob: " + strings.Repeat("x", 70*1024) + "\n---\n\n# Large Frontmatter Workflow\n" | ||
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Co-authored-by: pelikhan <[email protected]>
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