Table of Contents

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  1. Preface
  2. Understanding Pipeline Partitioning
  3. Partition Points
  4. Partition Types
  5. Pushdown Optimization
  6. Pushdown Optimization and Transformations
  7. Real-time Processing
  8. Commit Points
  9. Row Error Logging
  10. Workflow Recovery
  11. Stopping and Aborting
  12. Concurrent Workflows
  13. Grid Processing
  14. Load Balancer
  15. Workflow Variables
  16. Parameters and Variables in Sessions
  17. Parameter Files
  18. FastExport
  19. External Loading
  20. FTP
  21. Session Caches
  22. Incremental Aggregation
  23. Session Log Interface
  24. Understanding Buffer Memory
  25. High Precision Data

Advanced Workflow Guide

Advanced Workflow Guide

Session State of Operation

Session State of Operation

When you configure the session recovery strategy to resume from the last checkpoint, the Integration Service stores the session state of operation in the shared location, $PMStorageDir. The Integration Service also saves relational target recovery information in target database tables. When the Integration Service performs recovery, it restores the state of operation to recover the session from the point of interruption. It uses the target recovery data to determine how to recover the target tables.
You can configure the session to save the session state of operation even if you do not save the workflow state of operation. You can recover the session, or you can recover the workflow from the session.
The session state of operation includes the following information:
  • Source
    . If the output from a source is not deterministic and repeatable, the Integration Service saves the result from the SQL query to a shared storage file in $PMStorageDir.
  • Transformation.
    The Integration Service creates checkpoints in $PMStorageDir to determine where to start processing the pipeline when it runs a recovery session.
    When you run a session with an incremental Aggregator transformation, the Integration Service creates a backup of the Aggregator cache files in $PMCacheDir at the beginning of a session run. The Integration Service promotes the backup cache to the initial cache at the beginning of a session recovery run.
  • Relational target recovery data
    . The Integration Service writes recovery information to recovery tables in the target database to determine the last row committed to the target when the session was interrupted.


Updated November 14, 2019