Removing process instances from the Process database

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This topic only applies to BAW, and is located in the BAW repository. Last updated on 2025-03-13 12:15
To prevent disk-space issues and long waits in Process Portal, use the BPMProcessInstancesPurge command.

Before you begin

Run the query during an off period or maintenance window. When thousands of instances and data are purged, this process might cause a strain on the LSW_TASK and LSW_BPD_INSTANCE tables, which are core product tables. Running a clean-up job outside of normal business hours is a good practice.

If you want to archive data rather than deleting it, copy the data into a custom-built table outside of the product schema.

About this task

Completed process instances are not deleted from the system automatically. After a process instance is completed, the instance is typically no longer needed, so it can be removed from the Process database. The recommended approach is to use the BPMProcessInstancesPurge command. For information, see BPMProcessInstancesPurge command.

When an instance completes and all of its associated tasks are closed, future work is not possible with the instance. You cannot restart it, assign it to someone, or edit old work. When a user logs in to Process Portal, various tables are queried to gather data on the active tasks for that user. The operation involves full table scans, so even if only 35% of the data is relevant, it is going to take a while to pull the tasks needed for the user. If the other 65% is deleted, there is less data to scan.

If you do not delete the old completed instances, your team experiences slow performance on Process Portal and a potentially unusable state. Ignoring increases in database size cause an increase in backup time and disk space.

Deleting old instances affects only the search for history items from Process Portal. When you run the delete queries, you can specify to delete only completed processes that are older than 30 days. Store any data that you really need in either the performance database or in another system of record for auditing or metrics.

How often you delete old instances depends on the following factors:
  • How many instances are closed in a specified time period (for example, a week or month)
  • How large the data is in each task (including execution context and document attachments)
  • How many tasks there are in a process instance
The two largest reasons for runtime data growth are documents and execution context. If you have many documents and you must reference them later, consider a document management solution. Execution context is all the data that is carried from activity to activity. If the solution has many variables with large amounts of data, this scenario quickly uses database space. In this case, reviewing your solution is a good idea to reduce the amount of processor usage in the application.