Abstract: | This paper describes the ARS library package, which supports two implementation versions of an object-based system: a shared-variable and a message-passing version. The two versions have the same object structure and synchronisation but differ in their process structure and inter-process communication models. Thus, the mechanisms related to the uniform features are common for the two versions, but the process multiplexing mechanisms differ. As a consequence, the performance characteristics of the two versions of a system related to uniform features are similar, while those related to the process multiplexing differ significantly. We present an overview of the computational model supported by the ARS package, the internal structure of the package and compare overheads in two versions of an object-based system supported by the package. © 1998 John Wiley & Sons, Ltd. |