12 User Process Tracing

DTrace is a powerful tool for understanding the behavior of user processes. DTrace can be invaluable when debugging, analyzing performance problems, or simply understanding the behavior of a complex application. This chapter focuses on the DTrace facilities relevant for tracing user process activity and provides examples to illustrate their use.

This chapter contains the following topics:

• copyin and copyinstr Subroutines

• Eliminating dtrace Interference

• syscall Provider

• ustack Action

• uregs[] Array

• pid Provider