Using Extended Events to troubleshoot SQL Server issues

As a DBA, you'll encounter elusive performance, connectivity and locking problems that you'll need to troubleshoot. There are many tools that you can use such as Profiler. In addition to these tools, SQL Server 2008 offers extended events ("XEvents"), which you can use as a powerful tracing system. By default, the "system_health" extended events session is always on, and can provide you help to locate the source of trouble much faster

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samitha