164-java-profiling-verify

---
name: 164-java-profiling-verify
description: Use when you need to verify Java performance optimizations by comparing profiling results before and after refactoring — including baseline validation, post-refactoring report generation, quantitative before/after metrics comparison, side-by-side flamegraph analysis, regression detection, or creating profiling-comparison-analysis and profiling-final-results documentation. This should trigger for requests such as Verify performance fix; Verify the performance; Verify the memory; Verify the threading; Compare before and after profiling results; Check for performance regressions after refactoring. Part of Plinth Toolkit
license: Apache-2.0
---

# Java Profiling Workflow / Step 4 / Verify results

Verify performance optimizations through rigorous before/after comparison: ensure baseline and post-refactoring profiling data use identical test conditions, generate post-refactoring reports, compare metrics (memory, CPU, GC, threading), perform side-by-side flamegraph analysis, document findings in profiling-comparison-analysis-YYYYMMDD.md and profiling-final-results-YYYYMMDD.md, and validate success criteria.

**What is covered in this Skill?**

- Pre-refactoring baseline: run profiler with same load before changes
- Post-refactoring: generate new reports with identical test conditions
- Comparison: memory (leaks, allocations, GC), CPU (hotspots, contention), visual flamegraph comparison
- Documentation: profiler/docs/profiling-comparison-analysis-YYYYMMDD.md, profiler/docs/profiling-final-results-YYYYMMDD.md
- File naming: baseline/after suffixes, timestamp-based organization
- Validation: verify reports exist, compare metrics, identify regressions

**Scope:** Identical test conditions are critical. Document test scenarios. Validate application runs with refactored code before generating new reports.

## Constraints

Use identical test conditions between baseline and post-refactoring. Verify both report sets are complete. Document test scenarios.

- **CONSISTENCY**: Use identical test conditions and load patterns for baseline and post-refactoring
- **VALIDATE**: Ensure both baseline and post-refactoring reports exist and are non-empty before comparison
- **DOCUMENT**: Record test scenarios and load patterns for reproduction
- **BEFORE APPLYING**: Read the reference for comparison templates and validation steps
- **EDGE CASE**: If request scope is ambiguous, stop and ask a clarifying question before applying changes
- **EDGE CASE**: If required inputs, files, or tooling are missing, report what is missing and ask whether to proceed with setup guidance

## When to use this skill

- Verify performance fix
- Verify the performance
- Verify the memory
- Verify the threading
- Verify the GC
- Verify the profiling
- Compare before and after profiling results
- Performance benchmark
- Check for performance regressions after refactoring

## Workflow

1. **Read verification reference and confirm baseline data**

Read `references/164-java-profiling-verify.md` and verify baseline artifacts exist and are non-empty.

2. **Generate post-refactoring profiling data**

Run profiling with identical load/test conditions to produce comparable post-refactoring artifacts.

3. **Compare before/after metrics and visuals**

Perform quantitative comparisons for memory/CPU/GC/threading and side-by-side flamegraph analysis.

4. **Document final verification outcome**

Create comparison and final results reports with regressions, gains, and reproducible scenario details.

## Reference

For detailed guidance, examples, and constraints, see [references/164-java-profiling-verify.md](references/164-java-profiling-verify.md).