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This latch class is when a thread needs access to a data structure for the Persistent Version Store (PVS), when adding an off-row version to it in a database that is using Accelerated Data Recovery (ADR).

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Added in SQL Server version:


Removed in SQL Server version:


Extended Events latch_class value:

The map_key value in sys.dm_xe_map_values is 168 in 2017 RTM. After 2017 RTM, you must check the DMV to get the latest value as some map_key values have changed in later builds.

Other information:

This latch can become a contention point if you have enabled ADR in a database with many concurrent DML operations. In that case, consider whether the potential benefit of ADR for rolling back long-running transactions is worth the performance hit of contention on this latch.

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

  1. TBD

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

  1. TBD