When the IMA Service starts after restarting the server, it establishes a connection to the data store and performs various reads to update the local host cache. These reads can vary from a few hundred kilobytes of data to several megabytes of data, depending on the size and configuration of the farm.

To reduce the load on the data store and to reduce the IMA Service start time, Citrix recommends maintaining cycle boot groups of no more than 100 servers. In large farms with hundreds of servers, or when the database hardware is not sufficient, restart servers in groups of approximately 50, with at least a 10 minute interval between groups.

Note: If the Service Control Manager(Explanation given in below paragraph) reports that the IMA Service could not be started during a cycle boot of a Presentation Server but the service eventually starts, ignore this message. The Service Control Manager has a time-out of six minutes. The IMA Service can take longer than six minutes to start because the load on the database exceeds the capabilities of the database hardware. To eliminate this message, try rebooting fewer servers at one time.

The Service Control Manager (SCM) maintains a database of the installed services and driver services that allow the operating system to start successfully, and provides a unified and secure means of controlling them. The database, which is stored in the Windows system registry, includes configuration and security information about each service or driver service.