Modeling and Analyzing Resource-Sensitive Actors: A Tutorial Introduction

Part 1: Tutorial; International audience; Actor languages decouple communication from synchronization, which makes them suitable for distributed and scalable applications with flexible synchronization patterns, but also facilitates analysis. ABS is a timed actor-based modeling language which supports cooperative scheduling and the specification of timing- and resource-sensitive behavior. Cooperative scheduling allows a process which is executing in an actor to be suspended while it is waiting for an event to occur, such that another process in the same actor can execute. Timed semantics allows the specification of the temporal behavior of the modeled system. Resource-sensitive behavior takes a supply and demand perspective of execution, relating cost centers which provision resources to processes which require them. These modeling concepts have been used in ABS to model cloud computing, e.g., data-processing applications running on the Hadoop platform and micro-services running on containers orchestrated by Kubernetes. In this tutorial, we present ABS and its execution environment, and discuss the use of cooperative scheduling and resources in modeling cyber-physical systems and applications deployed on virtualized infrastructure.