XADM: Limiting Memory Usage of Exchange Server

You may use the Microsoft Exchange Performance Optimizer to limit the amount of memory that Microsoft Exchange Server uses, but you cannot manually set this value within the registry of an Exchange Server computer.

Microsoft Exchange Performance Optimizer includes an option to limit the amount of memory that Microsoft Exchange Server has access to. By default this value is set to zero, which allows Microsoft Exchange Server access to all of the available RAM on the server.

If you want to limit the amount of memory that Microsoft Exchange Server can access, you can run Microsoft Exchange Performance Optimizer and enter the amount of memory you want the Exchange Server computer to use. The value should be 24 MB or more. 32 MB or more is recommended.

The size of the Microsoft Exchange Server memory cache is adjusted automatically when you use the Performance Optimizer. By default, Microsoft Exchange Server uses all of the physical memory available. If you run other programs on your servers, you can restrict the amount of memory used by Microsoft Exchange Server.

When you run the Performance Optimizer, it analyzes the servers resources and configures the server as follows:

The Performance Optimizer detects the amount of physical memory in the server and calculates the size of the caches for the directory and the information store based on the information you provide about how the server will be used.

The default values for the directory and information store caches are appropriate for most installations. Although larger caches may provide better performance in some circumstances, performance depends on the amount of physical memory available.

Based on the values computed by Performance Optimizer, changes are made to the registry; these values cannot be manually computed and modified in the registry.