HarmonicAnalysisEngine: CI Performance Test Failure

by Alex Johnson 52 views

Introduction

In the realm of software development, Continuous Integration (CI) plays a pivotal role in ensuring the reliability and efficiency of applications. A crucial aspect of CI is performance testing, which helps identify bottlenecks and areas for optimization. When performance tests fail, it signals potential issues that need immediate attention. This article delves into a specific case where performance tests for the HarmonicAnalysisEngine in a CI environment have failed, causing concern and requiring a systematic approach to diagnose and resolve the problem. Understanding the root causes and implementing appropriate solutions are essential to maintain the stability and performance of the application.

📝 Overview

The main branch of our CI environment is currently experiencing failing performance tests. Specifically, the single-time calculation of the HarmonicAnalysisEngine is not completing within the expected 1ms, taking approximately 6.2ms instead.

Parent Issue: None (existing issue on the main branch)

🐛 Current Problem

CI Execution Result (Run 19433388327)

  • Job: test (18)
  • Step: Run unit tests (fast)
  • Result: 1 failed / 1341 passed

Failing Test

FAIL src/services/tide/__tests__/HarmonicAnalysisEngine.test.ts
  > HarmonicAnalysisEngine > パフォーマンステスト
    > TC-H025: 単一時刻計算が1ms以内

AssertionError: expected 6.228226999999606 to be less than 1

  387|       const endTime = performance.now();
  388|
  389|       expect(endTime - startTime).toBeLessThan(1); // <1ms
     |                                  ^
  390|     });

Details

  • Expected: < 1ms
  • Actual: 6.23ms
  • Difference: Approximately 6x slower
  • File: src/services/tide/__tests__/HarmonicAnalysisEngine.test.ts:389

🔍 Cause Analysis

Possible Causes

  1. CI Environment Performance
    • GitHub Actions' ubuntu-latest runners are shared resources.
    • Executed in Node.js 18 environment (test (18) job).
    • Potentially affected by other processes.
  2. Overly Strict Test Constraints
    • 1ms is a very tight constraint.
    • Prone to instability in CI environments.
    • Potentially successful in local environments.
  3. Implementation Performance Issue
    • Actual calculation might be slow.
    • However, other performance tests are successful:
      • TC-H026: 24-hour calculation within 100ms ✅
      • TC-H027: Extremum detection performance ✅

Understanding the CI Environment: To effectively diagnose the cause of the performance test failure, it's crucial to consider the environment in which the tests are running. CI environments, such as GitHub Actions, often use shared resources, meaning that the performance of the tests can be influenced by other processes running on the same infrastructure. This variability can lead to inconsistent results, especially when dealing with very tight constraints like 1ms. Furthermore, the specific configuration of the CI environment, including the Node.js version and any other installed dependencies, can also impact performance. By understanding these environmental factors, we can better assess whether the issue is due to the test itself, the implementation, or the CI environment's characteristics.

Evaluating Test Constraints and Implementation: In addition to the CI environment, it's essential to evaluate the test constraints and the implementation of the HarmonicAnalysisEngine. A constraint of 1ms for a single-time calculation is exceptionally tight and may not be realistic for all environments. It's possible that the test is too sensitive and prone to failure due to minor variations in performance. On the other hand, there might be genuine performance issues in the implementation that need to be addressed. Although other performance tests related to the HarmonicAnalysisEngine are passing, it's still possible that the single-time calculation has specific bottlenecks that are not present in the other tests. By carefully examining the test constraints and the implementation, we can identify potential areas for optimization and determine the most appropriate course of action.

✅ Correction Policy

Phase 1: Cause Identification (30 minutes)

  • [ ] Execute npm run test:fast in the local environment.
  • [ ] Confirm if TC-H025 succeeds.
  • [ ] Compare Node.js 18 and Node.js 20.
  • [ ] Verify if it fails only in the CI environment.

Phase 2: Implementation of Corrections (30 minutes - 1 hour)

Pattern A: Relaxing Test Constraints (Recommended)

  • [ ] Change the expected value from 1ms to 10ms.
  • [ ] Set a realistic value considering the characteristics of the CI environment.
  • [ ] Reason: 1ms is too strict for the CI environment.

Pattern B: Skipping the Test (Second Best)

  • [ ] Skip only in the CI environment.
  • [ ] test.skipIf(process.env.CI)('TC-H025: ...')
  • [ ] Reason: Performance tests are conducted locally.

Pattern C: Implementation Optimization (Long-Term Response)

  • [ ] Optimize the calculation logic of HarmonicAnalysisEngine.
  • [ ] Utilize caching.
  • [ ] Reason: Fundamental performance improvement.

Strategic Approaches to Resolving the Issue: When addressing the performance test failure, it's crucial to adopt a strategic approach that considers both short-term and long-term solutions. The initial phase should focus on identifying the root cause of the problem, whether it's related to the CI environment, overly strict test constraints, or the implementation itself. Once the cause is identified, the next step is to implement appropriate corrections. Relaxing the test constraints, as suggested in Pattern A, is a pragmatic approach that acknowledges the variability and limitations of CI environments. Skipping the test in the CI environment, as proposed in Pattern B, is a temporary workaround that allows development to continue while the underlying issue is investigated. However, the long-term goal should be to optimize the implementation, as outlined in Pattern C, to ensure that the HarmonicAnalysisEngine performs efficiently in all environments. By combining these strategic approaches, we can effectively resolve the performance test failure and prevent similar issues from occurring in the future.

Phase 3: Verification (30 minutes)

  • [ ] npm run test:fast succeeds locally.
  • [ ] Create a PR and verify in the CI environment.
  • [ ] Succeed in both test (18) and test (20).

📂 Files to Edit

Planned (In Advance)

  • [ ] src/services/tide/tests/HarmonicAnalysisEngine.test.ts (change expected value)
  • [ ] src/services/tide/HarmonicAnalysisEngine.ts (optimization, in case of Pattern C)

Results (During/After Completion)

(Update after starting work)

🧪 Verification Method

Local Environment

# Execute all tests
npm run test:fast

# Execute only the relevant test
npx vitest run src/services/tide/__tests__/HarmonicAnalysisEngine.test.ts

# Execute only performance tests
npx vitest run --grep "TC-H025"

CI Environment

  • Ensure that the test (18) job succeeds.
  • Ensure that the test (20) job succeeds.
  • Ensure that all 1341 tests succeed.

📊 Priority/Size

  • Priority: High (CI of the main branch is failing)
  • Estimated work time: 1-2 hours
  • Number of files: 1 file
  • Size: size:XS

🔗 Related Issues/PRs

💡 Remarks

  • This issue is unrelated to the merging of PR #130.
  • It is an existing issue on the main branch.
  • All other 1340 tests are successful.
  • Only performance test TC-H025 is failing.

📈 Recommended Approach

Pattern A (Relaxing Test Constraints) is recommended:

  • Easiest and safest
  • Considers the characteristics of the CI environment
  • Good balance with other performance tests (TC-H026: 100ms)
  • Change from 1ms → 10ms (10x margin)

Labels: bug, priority:high, size:XS, type:testing Responsible: @yuusuke0324

The Importance of Thorough Testing: In the intricate world of software development, thorough testing is paramount to ensure the reliability, stability, and performance of applications. Performance testing, in particular, plays a vital role in identifying bottlenecks, inefficiencies, and potential issues that may impact the user experience. When performance tests fail, it serves as a critical warning sign that requires immediate attention and a systematic approach to diagnose and resolve the problem. The case of the HarmonicAnalysisEngine performance test failure highlights the importance of continuous monitoring, proactive issue resolution, and a commitment to maintaining high-quality standards throughout the development lifecycle. By prioritizing testing and investing in robust testing infrastructure, organizations can minimize the risk of performance-related issues and deliver exceptional user experiences.

Conclusion: The failure of the performance test for the HarmonicAnalysisEngine in the CI environment underscores the complexities and challenges of modern software development. By adopting a systematic approach to cause analysis, correction implementation, and verification, the development team can effectively resolve the issue and prevent similar problems from recurring in the future. The recommended approach of relaxing the test constraints, while acknowledging the limitations of the CI environment, offers a pragmatic and efficient solution. However, the long-term goal should be to optimize the implementation of the HarmonicAnalysisEngine to ensure that it meets the required performance standards in all environments. Ultimately, a commitment to thorough testing, proactive issue resolution, and continuous improvement is essential to deliver high-quality, reliable, and performant software applications. For more information on CI and performance testing, visit this link.