The Integration Service stores the workflow state of operation when you enable the workflow for recovery or for suspension. When the workflow is suspended, the state of operation is in memory.
When you enable a workflow for recovery, the Integration Service stores the workflow state of operation in the shared location, $PMStorageDir. The Integration Service can restore the state of operation to recover a stopped, aborted, or terminated workflow. When it performs recovery, it restores the state of operation to recover the workflow from the point of interruption. When the workflow completes, the Integration Service removes the workflow state of operation from the shared folder.
The workflow state of operation includes the following information:
Active service requests
Completed and running task status
Workflow variable values
When you run concurrent workflows, the Integration Service appends the instance name or the workflow run ID to the workflow recovery storage file in $PMStorageDir.
When you enable a workflow for recovery the Integration Service does not store the session state of operation by default. You can configure the session recovery strategy to save the session state of operation.