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These session performance metrics are collected from the Dynamic Management View (DMV) sys.dm_exec_requests. For more information about individual metrics, see the corresponding Microsoft Developer Network (MSDN) article (http://msdn.microsoft.com/en-us/library/ms177648.aspx).
Access the Sessions view
You can access the Sessions view for a SQL Server instance by expanding the directory tree for the instance, and then selecting Sessions.
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