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Traces

• Generate log of time-stamped events.
  • Type, procedure name, destination task.
• Broad study of program behavior:
  • Examine communication relationships.
  • Localize sources of idle times.
  • Identify temporary hot spots.
• Postprocessing to obtain profile, count, interval timer information.
• Generation of higher-order statistics and summary data.
• Disadvantage: huge volume of data.
  • Thousands of megabytes for large program runs.
  • Probe effect: measuring changes behavior.
  • Extraction of relevant information difficult.