A decentralized approach for discovering runtime software architectural models of distributed software systems

Abstract

Abstract Context: Runtime software architectural models of self-adaptive systems are needed for making adaptation decisions in architecture-based self-adaptive systems. However, when these systems are distributed and highly dynamic, there is an added need to discover the system’s software architecture model at runtime. Current methods of runtime architecture discovery use a centralized approach, in which the process is carried out from a single location. These methods are inadequate for large distributed software systems because they do not scale up well and have a single point of failure. Objective and Method: This paper describes DeSARM (Decentralized Software Architecture discoveRy Mechanism), a completely decentralized and automated approach, based on gossiping and message tracing, for runtime discovery of software architecture models of distributed software systems. DeSARM is able to identify at runtime important architectural characteristics such as components and connectors, in addition to synchronous and asynchronous communication patterns. Furthermore, through its use of gossiping, DeSARM exhibits the properties of scalability, global consistency among participating nodes, and resiliency to failures. This paper demonstrates DeSARM’s properties and answers key research questions through experimentation with software architectures of varying sizes and complexities executing within a computer cluster. Results: DeSARM enables the decentralized discovery of runtime software architectural models of distributed software systems while exhibiting the properties of scalability, global consistency among participating nodes and resiliency to failures. Scalability is achieved through DeSARM’s ability to successfully discover software architectures of increasing sizes and complexities executing across node counts of increasing sizes. Global consistency among participating nodes is achieved by each node within the system discovering the complete software architecture independently but in coordination with each other. Finally, resiliency to failures is achieved by DeSARM successfully discovering the software architecture of the system in the presence of component failures.