System services design

The Sysrem Services provide some advanced functionalities, in addition to those provided by the Kernel. An example of such a service is the management of type definitions and hierarchies. The System Services in turn use the functionalities provided by the Kernel. As an example the system component providing type management services may use the Storage Subsystem for the storing and retrieval of type definitions. In particular the System Services are implemented as objects and therefore access to them by mean of the normal invocation mechanism as supported by the Kernel. It should be recalled that this invocation mechanism provides transparent access to all objects in the system, regardless of their locations on nodes. As a consequence a flexible system configuration results, because system services do not need to be located at every node of a COMANDOS system. This report describes the implementation specifications of three basic system services: - The Object Data Management System (ODMS), - The Type Manager (TpM), - The Name Service. These implementation specifications ONLY include those parts of the functional specifications (Deliverable D1-T3.2.2.1-870904) which we intend to implement before the end of the contract in March 1989. This report is composed of two documents: - A main document describing me basic components of the intended implementation. - An appendix document detailing the internal structure of these components.