Scope Revision Summary: Within-Mode Profiling¶
Date: 2026-01-08
Change: Performance profiling scope changed from comparative to within-mode analysis
What Changed¶
Before¶
Profiling tickets explicitly framed around comparisons: - "Investigate why Rust concurrent achieves 2.52x while Python achieves 3.74x" - "Comparison to Python wrapper baseline" - Optimization recommendations based on "matching Python's performance"
After¶
All profiling now within-mode analysis: - "What limits this implementation's performance?" - "Where does it spend time?" - "What are optimization opportunities in this mode?" - Optimization decisions separate in OPTIMIZATION_PROPOSAL.md
Affected Closed Tickets¶
✓ Salvageable Work¶
mrrc-u33.4 (Python single-threaded) - Status: Already refactored, complete ✓ - No further action needed
mrrc-u33.2 (Rust single-threaded profiling) - Status: Closed - Work product: RUST_SINGLE_THREADED_PROFILING_RESULTS.md (refactored) - Action: Adequate for within-mode analysis; no redo needed
mrrc-u33.3 (Rust concurrent profiling) - Status: Closed - Work product: RUST_CONCURRENT_PROFILING_RESULTS.md - Action: Refactoring in progress (mrrc-dpk.1)
⚠️ Refactored Away¶
mrrc-u33.1 (Comparative analysis) - Status: Closed with notes - Original: Explicitly comparative ("why does Python outperform Rust?") - Resolution: Closed; comparative analysis refactored to OPTIMIZATION_PROPOSAL.md - New equivalent: Work continues through individual profiling tasks (u33.7, u33.8, u33.9, u33.10)
Reorganized Open Tasks¶
Changed Status¶
| Ticket | Before | After | Reason |
|---|---|---|---|
| mrrc-u33.6 | Open (duplicate of u33.7) | Closed | Consolidated |
| mrrc-u33.1 | Open (comparative) | Closed | Refactored; work continues elsewhere |
Rescoped for Within-Mode Focus¶
| Ticket | Change |
|---|---|
| mrrc-u33.7 | Renamed/refocused: "Deep-dive analysis: Pure Rust single-threaded parsing bottlenecks" |
| mrrc-u33.8 | Refocused: "Rayon task scheduling efficiency" (within-mode questions) |
| mrrc-u33.9 | Refocused: "Memory bandwidth and cache efficiency" (within-mode analysis) |
| mrrc-u33.10 | Refocused: "Workload-dependent performance characteristics" (within-mode inflection points) |
Supporting Tasks¶
| Ticket | Purpose |
|---|---|
| mrrc-u33.2.2 | Flamegraph profiling for u33.7 |
| mrrc-u33.2.3 | Heaptrack memory profiling for u33.7 |
Documentation Changes¶
Created¶
- OPTIMIZATION_PROPOSAL.md - Optimization strategies and decisions (extracted from profiling)
- REFACTORING_NOTES.md - Refactoring guidelines and scope clarification
- ASSESSMENT_CLOSED_TICKETS.md - Analysis of closed tickets against new scope
- SCOPE_REVISION_SUMMARY.md (this document)
Refactored¶
- PROFILING_SUMMARY.md - Removed cross-mode comparison table
- PROFILING_PLAN.md - Removed comparative justification
- PHASE_2_DETAILED_ANALYSIS.md - Separated optimization proposals
- RUST_SINGLE_THREADED_PROFILING_RESULTS.md - Removed comparative questions
- README.md - Added refactoring status note
In Progress¶
- RUST_CONCURRENT_PROFILING_RESULTS.md (mrrc-dpk.1) - Remove "matches Python" framing
Key Principles Going Forward¶
Within-Mode Profiling Means: - ✅ Measure each implementation in isolation - ✅ Identify bottlenecks specific to that mode - ✅ Quantify costs and overheads - ✅ Ask "what limits performance in this mode?" - ✅ Provide data for optimization decisions
NOT Comparative: - ❌ Compare to other modes - ❌ Justify improvements by referencing other modes - ❌ Use cross-mode comparisons to reason about changes - ❌ Ask "why is mode X faster than mode Y?" - ❌ Mix profiling with optimization decisions
Work Status Summary¶
| Category | Status | Notes |
|---|---|---|
| Completed & Delivered | ✓ | pymrrc single-threaded profiling (mrrc-u33.4) |
| Completed & Refactored | ✓ | Rust single-threaded profiling (mrrc-u33.2) |
| Completed & Pending Refactor | ⏳ | Rust concurrent profiling (mrrc-u33.3) → mrrc-dpk.1 |
| Closed & Refactored | ✓ | Comparative analysis (mrrc-u33.1) → moved to OPTIMIZATION_PROPOSAL.md |
| Reorganized as Within-Mode | ✓ | mrrc-u33.6, u33.7-u33.10 rescoped |
| Documentation Cleaned | ✓ | All profiling docs refactored for scope |
Next Steps¶
- Complete mrrc-dpk.1 - Finish refactoring RUST_CONCURRENT_PROFILING_RESULTS.md
- Execute remaining profiling - mrrc-u33.7, u33.8, u33.9, u33.10 tasks
- Consolidate findings - Synthesize all profiling into baseline metrics
- Plan optimizations - Use OPTIMIZATION_PROPOSAL.md as guide
References¶
- Epic: mrrc-u33 (Performance optimization review)
- Refactoring task: mrrc-dpk (Refactor profiling documentation)
- Refactoring subtask: mrrc-dpk.1 (RUST_CONCURRENT_PROFILING_RESULTS.md)
- Documentation: docs/design/profiling/
- Optimization strategy: docs/design/OPTIMIZATION_PROPOSAL.md