SQL Server General Statistics: User Connections – The number of user connections to the SQL Server. This is a good way to trend when the server is used most during the day.
SQL Server: SQL Statistics: Batch Requests/Sec – This is a good indicator of how busy your SQL server is. If this number is over 1000 then you have a pretty busy SQL server.
SQL Server Buffer Manager Objects: Cache Size (pages) – This monitors how much physical RAM is devoted to the data cache of the SQL server. This is measured in pages, so multiply this number by eight to see how much physical RAM is being taken up.
These three performance counters should give you a pretty good start on monitoring your Microsoft SQL Server.
Chris Sanders is a network consultant for KeeFORCE, one of the most popular network consulting firms in western Kentucky. Chris is the author of the book Practical Packet Analysis as well as several technical articles. His personal website at www.chrissanders.org contains a great deal of information, articles, and guides related to network administration, network security, packet analysis, and general information technology.