Database instrumentation must be implemented by developers, but is used by administrators. In this session, I describe why instrumentation is so valuable to both groups and how it can become a part of optimising a system.Debug code reports that something executed, but instrumentation is applied to the database session, and gives context to the database metrics. In Oracle, this is the module and action attributes.
SQL trace with a watchpoint for a particular value for specific values of module and action. On Enterprise Edition, the module and action are reported in AWR and ASH.
Module and action can be used to map sessions to resource manager plan consumer groups. They can exact-match or pattern-match.
Sometimes, you may need to add instrumentation to a packaged application without changing code, by using database triggers and Fine-Grained Audit.
The instrumented performance metrics can then be profiled in SQL by module and action. Sometimes, it is necessary to simplify the instrumentation using regular expressions.
The presentation was given at UKOUG 2025. It is also available in a pdf file in pdf format.