The Performance Schema is the main source of diagnostics information related to performance in MySQL. It was first introduced in MySQL in version 5.5, then heavily modified to its current structure in version 5.6, and since then gradually improved in 5.7 and 8.
This chapter introduces and provides an overview of the Performance Schema, so it is clear how it works when the Performance Schema is used throughout the remainder of the book. Close relatives to the Performance Schema are the sys schema which will be discussed in the next chapter and the Information Schema ...
