Pull request

[muhammadokashapak]

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What is the most appropriate course of action when a developer submits a pull request that addresses a critical bug, but also introduces a significant performance regression that is only apparent under high-load conditions?

[hassanzaibjadoon]

Handling a Pull Request with a Critical Bug Fix and a Performance Regression

When a pull request (PR) addresses a critical bug but introduces a significant performance regression under high-load conditions, here’s the best approach:

1. Acknowledge the Issue

• Thank the developer for addressing the critical bug.
• Clearly communicate the importance of resolving both the bug and the performance regression to maintain project stability.

2. Review and Identify the Cause

• Use performance testing tools or benchmarks to analyze and pinpoint the source of the regression.
• Provide detailed feedback in the PR comments about the performance issue.

3. Propose a Temporary Solution

• If the critical bug must be fixed urgently:
  • Merge the PR into a temporary or feature branch.
  • Notify the team and document the regression as a known issue.
  • Work on a follow-up PR to address the performance regression before releasing the fix to production.

4. Collaborate with the Developer

• Encourage the developer to address the performance regression within the same PR, if feasible.
• Offer guidance or pair programming to help resolve the issue efficiently.

5. Consider Alternative Approaches

• Evaluate if there’s a simpler solution to fix the bug without introducing performance issues.
• Suggest splitting the PR into two: one for the bug fix and another to explore performance optimization.

6. Test Thoroughly Before Merging

• Run extensive tests under high-load conditions to ensure both the bug is fixed and performance regression is resolved.
• Once the issue is addressed, proceed with merging the PR into the main branch.

7. Improve Processes

• Reflect on how the regression was missed. For example:
  • Add high-load performance tests to the CI/CD pipeline.
  • Update code review guidelines to include performance considerations.

This balanced approach ensures the critical bug is addressed promptly while maintaining the project's overall quality and performance.