To test applications under full production load before launching, what methodology should be applied?

The methodology that best fits the requirement of testing applications under full production load before launching is shadow testing with continuous deployment. Shadow testing allows you to run a new version of an application in parallel to the current production version without affecting the actual user experience. This means you can monitor the performance of the new version under real traffic conditions while the existing version continues to serve users.

This approach is particularly advantageous because it simulates production load and gives you the opportunity to identify any issues that might only arise under full production conditions. You can analyze metrics and logs generated by the shadow version, gain insights into how it behaves under pressure, and ensure it can handle the expected user load before the actual launch.

Continuous deployment supports this methodology by allowing you to release updates to production systems automatically, maintaining a fast and efficient pipeline for your application without downtime. By using shadow testing in conjunction with continuous deployment, you can ensure that any potential issues are addressed before the application goes live to all users, which enhances reliability and user satisfaction.