Domain manager domain (DM)

The domain manager domain (also sometimes known simply as "domain manager") is responsible for maintaining, through the use of catalog services, permanent information about individual domains.

Each domain has certain permanent characteristics. These are stored on the local catalog and include the name, token, and ID; these characteristics are unique for each domain. Each domain also has volatile characteristics (including the phase number and the status), which are not stored on the catalog.

The domain manager attaches initialization and termination tasks for other domains. It maintains phase information of the other domains to allow controlled introduction and withdrawal of domain services during initialization and termination. For each domain, a phase number denotes the set of services that are available from the domain. An increased phase number would correspond to an increased set of available functions.

During initialization, the system phase is the minimum of the phase numbers of the active domains. During shutdown, the system phase is the maximum of the phase numbers of the active domains.

The domain manager also maintains and manages a queue of waiting domains (called "waiters"); these waiting domains are waiting for a specific domain to reach a certain phase or for the system phase to reach a certain level.

[[ Contents Previous Page | Next Page Index ]]