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This latch is is when a thread is waiting for access to create a new identity value during an insert.
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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 143 in 2012 and 2014 RTM. After 2014 RTM, you must check the DMV to get the latest value as some map_key values have changed in later builds.
Anecdotal evidence shows that this latch can become a bottleneck when doing parallel build loads into a table that has an identity column.
Known occurrences in SQL Server (list number matches call stack list):
Abbreviated call stacks (list number matches known occurrences list):