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This wait type is from a background task related to the Launchpad service that allows external scripts to be run as part of SQL Server Machine Learning Services. Each wait is for 300 seconds. More info on Launchpad is here.

(Books Online description: N/A)

Questions/comments on this wait type? Click here to send Paul an email, especially if you have any information to add to this topic.

Added in SQL Server version:

Azure SQL Database

Removed in SQL Server version:


Extended Events wait_type value:

Maps to the EXTENSIBILITY_CLEANUP_TASK map_value in sys.dm_xe_map_values.

The map_key value in sys.dm_xe_map_values is  1318  as of late 2019. You must check the DMV to get the latest value as some map_key values have changed in later builds.

Other information:

This wait type is one that I usually filter out as a benign wait when doing wait statistics analysis. It will usually show up as one of the top waits on Azure SQL Database and SQL Server 2019 and can be safely ignored.

Known occurrences in SQL Server (list number matches call stack list):

  1. Waking up and checking if there’s anything to do.

Abbreviated call stacks (list number matches known occurrences list):

  1. SOS_Task::PostWait+0x6f