The Memory Manager object in Microsoft SQL Server provides counters to monitor overall server memory usage. Monitoring overall server memory usage to gauge user activity and resource usage can help you to identify performance bottlenecks. Monitoring the memory used by an instance of SQL Server can help determine:

* If bottlenecks exist from inadequate physical memory for storing frequently accessed data in cache. If memory is inadequate, SQL Server must retrieve the data from disk. * If query performance can be improved by adding more memory or by making more memory available to the data cache or SQL Server internal structures.