Horst F. Wedde, Kwei-Jay Lin, Aloysius K. Mok und Krithivasan Ramamritham
A Completely Integrated Approach to Developing, Implementing, Evaluating Distributed Active Database Management and its OS Support
WRTP’99, 24th IFAC/IFIP Workshop on REAL TIME PROGRAMMING, 1999
This paper constitutes a work-in-progress report on the first, mostly conceptual phase of a major international effort in building and evaluating a distributed testbed for database application systems in safety-critical real-time environments. Given that safety/ reliability requirements and realtime constraints are in conflict there cannot be a closed form solution or design, and all system functions have to dynamically adapt to the unpredictable environmental situation in safety-critical realtime systems. Over the past years groups headed by the authors had pursued novel concepts and approaches on a novel tailored LINUX kernel, safety-critical application operating system support (MELODY project) and Active Database levels (concurrency control under data replication). In the research project a complete integration of these achievements from the basic OS kernel through the application levels is the major theme. While quite a number of research and design problems stemming from the partial insights or incomplete functionality on the various levels posed serious challenges the integration itself requires, and gives rise to, extensions, modifications, or refinements of the functions involved for ensuring system survivability. The paper will describe the technical details of these implications from the integration for the whole project as well as the stepwise design and evaluation of the different functions and models.- To our knowledge this is the first fully integrative attempts in the area of distributed safety-critical real-time systems.