Most non-trivial applications depend a great deal on third-party libraries for various functionality, such as logging, serving web requests, connecting to databases, writing to message queues, and so on. Many of these libraries not only carry out parts of critical business functionality but also appear in the performance-sensitive areas of our code, impacting the overall performance. It is imperative that we choose libraries wisely (with respect to features versus performance trade off) after due performance analysis.

The crucial factor in choosing libraries is not identifying which library to use, rather it is having a performance model of our applications and having the use cases benchmarked under representative load. Only benchmarks can tell us whether the performance is problematic or acceptable. If the performance is below expectation, a drill-down profiling can show us whether a third-party library is causing the performance issue. In Chapter 6, Measuring Performance...