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When a trace is started, DB2 formats records containing the requested information. After the information is prepared, it must be externalized. DB2 traces can be externalized to six destinations:

1. GTF GTF (Generalized Trace Facility) is a component of MVS and is used for storing large volumes of trace data.
2. RES RES is a wraparound table residing in memory.
3. SMF SMF (System Management Facility) is a source of data collection used by MVS to accumulate information and measurements. This destination is the most common for DB2 traces.
4. SRV SRV is a routine used primarily by IBM support personnel for servicing DB2.
5. OPn OPn (where n is a value from 1 to 8 ) is an output buffer area used by the Instrumentation Facility Interface (IFI).
6. OPX OPX is a generic output buffer. When used as a destination, OPX signals DB2 to assign the next available OPn buffer (where X is a number between 1 and 8 ).

The Instrumentation Facility Interface (IFI), which is a DB2 trace interface, enables DB2 programs to read, write, and create DB2 trace records and issue DB2 commands. Many online DB2 performance monitors are based on the IFI.

A synopsis of the available and recommended destinations for each DB2 trace type is provided in the following table. Y indicates that the specified trace destination is valid for the given type of trace; N indicates that it is not.