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Added in SQL Server version:
Removed in SQL Server version:
Extended Events wait_type value:
The map_key value in sys.dm_xe_map_values is 241 in 2008 and 2008 R2, 248 in 2012, and 255 in 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.
I have not seen this wait type be a noticeable contention point.
Known occurrences in SQL Server (list number matches call stack list):
- Unknown. It doesn’t make sense that this wait is waiting for a flush of the log cache, as these are done asynchronously and tracked through WRITELOG waits.
Abbreviated call stacks (list number matches known occurrences list):