Identifying application problems with trace displays

Enter one of the following views by typing the view name on the COMMAND line.

• CT (Current traces)

  The CT view lists all currently active or complete trace requests. From this view, you can also execute the following actions for a trace:

  • Show defined trace options (W)
  • Modify a trace (M)
  • Switch to another trace (I)
  • Stop a trace (Z)
  • Purge a trace (P)
  • Replicate a trace (R)
  • Quiesce a trace (Q)

  On this view you can see the trace data as it is being collected. After the trace is complete, the data remains available until you purge the trace.

  Trace data is posted to the display buffer only when the accounting record is written.

  If you are tracing a longer running thread (detail), you can view the detail events as they occur with the UTRAC display. (Select the current USERS analyzer display, line select the detail display (DUSER) for your thread, and expand to UTRAC.)

  When you trace long-running threads, logging is recommended so that data is not lost because of buffer shortages. The data should also be viewed from the logs instead of the buffers, which is available from the HT view.

• HT (History traces)

  The HT view lists all known trace log data sets. Traces that are logged are also accessible through this view. From this view, you can also execute the following actions for a trace:

  • Show defined trace options (W)
  • Print a trace (P)
  • Delete a trace (D)
  • Reset a trace (E)
  • Verify a trace (V)
  • Archive a trace (A)
  • Free a trace (F)

  You can view your trace when it is running, after it is complete, and even after you have purged the original trace request. On the HT view you can compare different tests (even if they were run month or more apart), without keeping stacks of paper.

  From the log you can recall the data online or print selected reports. The trace log data sets are displayed in descending order by date and time, so you can easily find a newly created log. If you are looking for an older log, you can sort the display by any of the columns.

  Note

  The same summary trace thread accounting data that is shown in the full-screen LTRAC and STRAC displays is also available in windows mode views, as described in Analyzing-recent-workload-history. However, when analyzing applications with a detail trace, it is simpler to stay in full-screen mode.

  The following figure summarizes many of the ways you can navigate among the trace displays that are accessed from the CT and HT views.