In JES2, there are various processes that have trace points. When enabled, these points give information about JES2 registers, buffers, control blocks, and other pertinent items. During JES2 initialization, you direct JES2 to trace its activity by using the TRACE(n) and TRACEDEF initialization statements. Another way of establishing traces is by entering the $S TRACE(n), $P TRACE(n), and $T TRACEDEF commands. See z/OS MVS Initialization and Tuning Reference and z/OS JES2 Commands for information about the syntax of initialization and z/OS JES2 Commands for statements and commands related to tracing.

You can access trace data in two ways: in a dump of unformatted trace tables residing in the extended common storage area (ECSA) and in formatted system output.Formatting the trace information for system output is known as “logging”.