Evaluating Concurrency Options in Software Specifications

An approach called PERFECT is described which evaluates the feasibility of proposed software concurrency architectures for a set of scenarios and a set of quality-of-service requirements. An evaluation is performed by constructing and simulating a virtual implementation which conforms to the specified behaviour and the specified concurrency architecture. For simulation, the execution of application activities and kernel primitives must be sequenced for each concurrent thread. The approach is successfully demonstrated on specified scenarios for a Group Communication Server. 1 Introduction It is normal to establish a concurrency architecture before beginning to design software, and this is often done on the basis of inadequate information. A poor choice at this stage will limit the performance of the design. Too many concurrent processes will introduce excessive overhead for process switching, communication, and data protection while too few may introduce important delays due to non-u..