Jochen Joswig Discusses Sustainable Testing Strategies at OOP Conference

Optimizing Test Execution

Jochen Joswig, in his DevGreenOps talk at the OOP Conference, outlined methods for sustainable testing. The core idea involves setting up a testing strategy that minimizes the number of executed tests, thereby reducing both time and energy consumption. This approach aligns with principles of minimalism and efficiency in software development.

Fail-Fast and Targeted Testing

A key recommendation is to design testing strategies for fast and early failure. If a unit test fails, subsequent integration or end-to-end tests can be skipped, saving resources. Joswig also suggested executing only tests relevant to changed code, particularly in monorepo environments. For example, if only frontend code is modified, backend tests are not necessary.

Monitoring and Static Analysis

To further improve test setups, Joswig proposed tracking the energy consumption of individual tests. This data can be fed into observability stacks to flag methods or runs exceeding energy thresholds, prompting re-engineering for performance optimization. If direct energy consumption tracking is not possible, proxy metrics like MB transferred, time, CPU, and memory utilization can be used.

Identifying Inefficiencies with Static Code Analysis

Joswig recommended using static code analysis to identify inefficiencies, such as backend calls or database queries within loops. He mentioned Creedengo, an open-source SonarQube plugin supporting Java, Python, JavaScript, and C#, as a tool for this purpose. Closed-source alternatives may offer broader support for detecting code inefficiencies.