| Providing multiprocessor capability to the class of computers commonly referred to as personal workstations is the next evolutionary step in their development.;Uniprocessor workstations limit the user in throughput, reliability, functionality, and architecture. Multiprocessor workstations have the potential of increasing system throughput. A multiprocessor system with expanded architecture derived from a set of heterogeneous processors gives the user a diverse application base within a single system. The replication and diversity offered in systems of this design, when coupled with fault-tolerant design techniques, enhances system reliability.;A heterogeneous multiprocessor architecture is presented which combines loosely- and tightly-coupled configurations (multicomputer and multiprocessor). This architecture provides for incremental growth of the system, either by static or dynamic reconfiguration.;The software view of the system is that of an object-oriented environment. The object-oriented approach is used to unify the heterogeneous nature of the system. The process is the unit of concurrency in the system and cooperating concurrent processes are supported. A set of system primitives are provided to support the requirements of a heterogeneous multiprocessing environment. A virtual machine layer controls the distribution of processes and allocation of resources in the system. A virtual network is used to provide communication paths and resource sharing. The virtual network is designed to be bridged to an external physical network. The system requirements for a secure and reliable operating environment are incorporated into the design.;This system utilizes "hardware porting" as a means to overcome the lag of software support for hardware advances. Rather than software port an entire application base to a new system architecture, hardware porting brings the required instruction set architecture to the applications.;This heterogeneous multiprocessor architecture builds on a popular system architecture, the scIBM PS/2 with the Micro Channel system bus. Incorporating a second bus, the scSCSI bus, as a system extension is explored. |
