How can you ensure that performance issues are caught early in application development with CI?

Software performance starts with the quality and mentality of the developer team. If a team continuously considers performance when choosing tools, design, architecture, development, testing, and deployment, they'll have fewer performance concerns for their app. A great team builds a great performing application. Continuous monitoring is crucial. Set up alerts to notify developers of performance degradation, and use analysis reports to forecast and proactively address future scenarios, mitigating major failures. Additionally, create a disaster recovery plan outlining recovery procedures and target restoration times for optimal system recovery speed.

Catching performance issues early in application development is crucial to prevent them from escalating into more significant problems later on. Based on my XP, here are some strategies to ensure early detection: - Automated Performance Tests - Unit Testing with Performance Assertions - Threshold Monitoring - Profiling Tools - Code review - Static Code Analysis...

Establish performance baselines for the application, defining acceptable thresholds for key performance metrics based on business requirements and user expectations. These baselines serve as benchmarks for comparing performance test results and identifying deviations.

"Premature optimization is the root of all evil." I would argue that the time potentially invested in the code design "that maximizes your performance" can be better spent at setting up a performance testing environment. Obviously it is always a good idea to avoid unnecessary constructs and use tools fit for purpose but there is no need to overthink things from day one. “If it ain't broke, don't fix it.” Above applies to tools used as well. Do not spend time on setting up fancy tooling if you do not see a clear use case for using them. Deliver a simple solution quicker, allow CI performance tests to pick up bottlenecks and only then focus on optimizing those specific areas.

Considerations for Security and Compliance: While caching and compression enhance performance, it's essential to implement proper security measures to protect sensitive financial data from unauthorized access or leakage. Compliance requirements such as GDPR, PCI DSS, and SOC 2 may impose constraints on caching and compression practices, necessitating thorough risk assessments and mitigation strategies.

Testing unpredictable scenarios is really important. I worked on a system which is too fast when data is less but quickly becomes unimaginably slower with more data. As a developer if you don't test the edge case with lots of data and ship to production, what happens is your customers get the pain of bad performance and report the issue & then only you know about it! So either you catch the issue first, or your customers will.

In my experience, Include performance tests in your CI pipeline to detect regressions in response time and resource usage. Use static code analysis tools to identify potential performance bottlenecks and inefficient code patterns and database queries during the development process. Integrate monitoring tools into your CI pipeline to track application performance metrics and detect any deviations from baseline performance.