There are typically big gaps between the theoretical and practical performance limits. The challenge is how to enable systems to attain their theoretical performance level under any circumstance. The performance level required can suffer due to various reasons. This includes the poor system design, bugs in software, network bandwidth, third-party dependencies, and I/O access. The middleware solutions such as adapter, connector, and driver also contribute to the unexpected performance degradation of the system. The system's performance has to be maintained under any loads (user, message, and data). There are several metrics such as request per second (RPS) and transaction per second (TPS). Performance testing is one way of recognizing the performance bottlenecks and adequately addressing them. The testing is performed in the pre-production phase.
Now, the software is functioning in production servers, and the thing to do here is to continuously and...