Jump label

Service navigation

Main navigation

You are here:

Sub navigation

Main content


Horst F. Wedde und Jon A. Lind
Performance-Driven Design and Analysis for Distributed Mission-Critical Systems
IFAC Safety and Reliability in Emerging Control Technologies, S. 151-162, International Federation of Automatic Control, Daytona Beach, Florida, USA, 1995-11-3


Mission-critical systems typically operate in unpredictable environments. Requirements for safety and reliability are in conflict with those for real-time responsiveness. Due to unpredictable environmental needs there there is no static trade-off between measures o accomodate the conflicting objectives. Instead every feature or operating system service has to be adaptive. Finally, for any design problem, there cannot be any closed-form (formal) approach taking care at the same time of (external) time constraints or deadlines, and the synchronization requirements in the distributed design. The reason is that these two aspects are casually independent.

In this situation we worked out a heuristic experimental, performance-driven and performance-based methodology that allows in an educated way to start with a coarse system model, with accurate logical expectations regarding its behavior. Through experiments these expectations are validated. If they are found to successfully stand the tests extended expectations and model features are generated for refining the previous design as well al its performance criteria. The refinement is done in such way that previous experimental configuration are extreme model cases or data profiles which both logically and experimentally are to reproduce the behavior of the previous modelling step. Thus the novel performance aspects or tendencies could then unambiguously be attribued to the influences of the refined model features. We termed this methodology Incremental Experimentation. As a general methodology it relies on a principle of comparative performance studies rather than on relistic data for narrow application ranges.

The paper describes how we applied a 6-step design and refinement procedure for developing, analyzing, and evaluating our distributed operating system MELODY that exhibits novel services for supporting real-time and mission-critical applications in unpredictable environments. Experimental setups and theme-related findings are discussed in particular.