Scheduled Extract Refresh Intermittently Fails Without Error Message
Published: 21 Oct 2016 Last Modified Date: 21 Jul 2020
When published extracts are scheduled to refresh frequently throughout the day, some extracts are not updating as frequently as expected. Additionally, the message "[datasource name extract refresh] is already queued. Not queuing a duplicate" appears in the backgrounder log manytimes.
One of the following options may resolve the issue:
If it is important to keep data as fresh as possible, consider making a Live Connection to the database to prevent constant extract refreshes.
Using the Background Tasks for Extract report in Tableau Server, identify extacts that take longer then the Refresh Window to process. If an extract takes 20 minutes to complete, having it refresh every 15 minutes will cause a backgrounder to become monopolized by that single extract refresh.
Decrease the frequency of the extract refreshes. If the extracts are all being refreshed in 15-minute increments, increase to 30-minute schedules
Reconfigure Tableau Server processes to increase the backgrounder count
Note: If there are no available system resources, increasing the backgrounder process count will not resolve the issue.
The Backgrounder is overloaded and cannot complete the jobs in the time available.
Search the Backgrounder log folder for the phrase "Storing to repository" to find instances of successful extract refreshes
Search the Backgrounder log folder for the phrase "already queued. Not queuing a duplicate" to find instances of extract refreshes being triggered when already running
There are no error messages presented in the Background Tasks for Extracts report.