OpenTP1 acquires the performance verification trace for events of services operating on OpenTP1. The performance verification trace is used to improve efficiency of performance verification and troubleshooting.

The prfget command acquires the trace. The prfed command edits and outputs the acquired trace. The prfget command outputs the performance verification trace in binary format to a UNIX file. The prfed command converts the trace from binary format to character format and then edits and outputs the trace. The prfed command is used to view the details of the trace.

The features of the facility for acquiring the performance verification trace are as follows:

• You can trace events across nodes and processes.
• You can verify performance of processing by tracing each internal event, not by tracing each API.

You can use an output event ID to determine when the trace information is acquired. For the event IDs and the timing of acquiring the trace, see L. Acquiring Performance Verification Traces.

You must install TP1/Extension 1 to use this facility. Without TP1/Extension 1 installed, this facility may not operate correctly.

Notes

• Trace information is not passed for normal restart and hot standby.
• The facility for acquiring the performance verification trace does not perform locking when acquiring trace information so that online performance is not affected. Accordingly, if contention for trace acquisition occurs in a multi-processor environment, some trace information may be lost or invalid trace information may be acquired. When you use the prfed command to edit trace information, an error code is displayed for invalid trace information.

The following figure shows the flow of performance verification trace file operation by using the function that acquires the performance verification trace.

Figure 3-27 Flow of performance verification trace file operation

1. PRF trace data output during online operation is stored as files with the file name prf_nnn^#1 under the directory $DCDIR/spool/dcprfinf. The prf_file_size operand specifies the maximum size of each file, and the prf_file_count operand specifies the number of files. When a file reaches its capacity during online operation, the file is swapped and subsequent traces are acquired to the new file.
2. When OpenTP1 shuts down, the files prf_nnn.bk2^#2 in $DCDIR/spool/save are moved to prf_nnn.bk1.^#2
3. The files prf_nnn ^#1 in $DCDIR/spool/dcprfinf are copied to $DCDIR/spool/save under the name prf_nnn.bk2.^#2
   

   #1

   nnn: A number, starting from 001 and having the value specified for the prf_file_count operand as its upper limit.

   #2

   nnn: Value corresponding to the file name at the backup source.

Organization of this subsection

(1) Performance verification traces acquired by OpenTP1

(2) Backing up performance verification trace files

(3) Disabling backup of performance verification trace files