[From SQLServer Performance
SQL Server 2005 performance can be tracked and monitored by using performance counters. The performance counters can be displayed by either the System Monitor (PERFMON) tool, or by using the sys.os_exec_performance_counters Dynamic Management View (DMV). This DMV is new with SQL Server 2005. This article will explore the different counters exposed by this DMV and how you can use this DMV to monitor various performance aspects of SQL Server.
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