Trace Destinations

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 written to six destinations:

GTF (Generalized Trace Facility) is a component of MVS and is used for storing large volumes of trace data.

RES	RES is a wraparound table residing in memory.
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.
SRV	SRV is a routine used primarily by IBM support personnel for servicing DB2.
OP n	OP n (where n is a value from 1 to 8) is an output buffer area used by the Instrumentation Facility Interface (IFI).
OPX	OPX is a generic output buffer. When used as a destination, OPX signals DB2 to assign the next available OPn buffer (OP1 to OP8).

The Instrumentation Facility Interface, 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.

Consult Table 24.2 for a synopsis of the available and recommended destinations for each DB2 trace type. Y indicates that the specified trace destination is valid for the given type of trace; N indicates that it is not.

Table 24.2. DB2 Trace Destinations

Type of Trace	GTF	RES	SMF	SRV	OP n	OPX	Recommended Destination
Statistics	Y	N	Default	Y	Y	Y	SMF
Accounting	Y	N	Default	Y	Y	Y	SMF
Audit	Y	N	Default	Y	Y	Y	SMF
Performance	Y	N	Default	Y	Y	Y	GTF
Monitor	Y	N	Y	Y	Y	D	OP n
Global	Y	Default	Y	Y	Y	Y	SRV