Tracking Correlation IDs with Volatile Tracking

The Process Engine stores correlation IDs in server memory. Each correlation ID is associated with the process instance ID for a running process.

When the Process Engine receives an external document for a process that uses a correlation ID, the Process Engine runs the correlation service for the appropriate step and compares the correlation ID to the correlation IDs in server memory.

If the ID matches an ID for a running process, the Process Engine loads the external document content into server memory and the server executes the step as part of the running process.

If the ID does not match an ID for a running process, the Process Engine creates a process instance ID, stores the process instance ID and the correlation ID in server memory, and starts a new process.