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Added in SQL Server version:
Removed in SQL Server version:
Extended Events latch_class value:
Maps to the AM_IOAFF_READAHEAD¬ map_value¬†in¬ sys.dm_xe_map_values.
The¬ map_key¬†value in¬ sys.dm_xe_map_values¬ is 19 in 2008 and 2008 R2, and 14 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.
Known occurrences in SQL Server (list number matches call stack list):
Abbreviated call stacks (list number matches known occurrences list):