PERFORMANCE MODELING OF REAL-TIME MULTIPROCESSORS WITH TIME-SHARED BUSES
Original Publication Date: 1984-Nov-01
Included in the Prior Art Database: 2005-Sep-16
Software Patent Institute
Related PeopleAuthors: Other Related People:
The workload effects on computer performance are addressed for a highly reliable unibus multiprocessor used in real-time control. Because of the strict performance criteria required by a system of this type, it would be desirable to be able to determine the significant effects of workload distribution and scheduling on performance. As an approach to studying these effects, a modified stochastic Petri net (SPN) is used to describe the synchronous operation of this system. From this model the vital components affecting performance can be determined. However, because of the complexity in solving the modified SPN, a simpler model is constructed that presents the same critical aspects. This model is a closed queueing network. It consists of multiserver nodes and a non- preemptive priority queue. The use of this model for a specific application requires the partitioning of the workload into job classes. The steady state solution of the queueing model directly produces useful results, such as idle processing time, system bus contention, and bus queueing times, that are necessary in any performance evaluation. The use of this model in evaluating an existing system, the Fault Tolerant Multiprocessor (FTMP), is outlined with some experimental results.