Understanding Historical Performance Data

The system stores historical data from the moment a PMU finishes processing or an event occurs. When the archive program runs (PSPM_ARCHIVE), it either deletes the historical data or moves it to the archive tables.

Analyzing historical data can help you:

• Identify trends.

  By comparing historical data, you can spot upward and downward performance trends.

• Investigate past user complaints.

  For example, a user may complain that performance was slow during the previous week. You search historical performance data to find the PMUs that were generated by the user at a specific time a week ago.