arXiv subjects

David Garlan

Publications and source records attributed to David Garlan.

22 records · Page 2Linked to original sources

arXiv2019

Developing Self-Adaptive Microservice Systems: Challenges and Directions

A self-adaptive system can dynamically monitor and adapt its behavior to preserve or enhance its quality attributes under uncertain operating conditions. This article identifies key challenges for the development of microservice applications as self-adaptive systems, using a cloud-based intelligent video surveillance application as a motivating example. It also suggests potential new directions for addressing most of the identified challenges by leveraging existing microservice practices and technologies.

cs.SE↗

arXiv2019

Machine Learning Meets Quantitative Planning: Enabling Self-Adaptation in Autonomous Robots

Modern cyber-physical systems (e.g., robotics systems) are typically composed of physical and software components, the characteristics of which are likely to change over time. Assumptions about parts of the system made at design time may not hold at run time, especially when a system is deployed for long periods (e.g., over decades). Self-adaptation is designed to find reconfigurations of systems to handle such run-time inconsistencies. Planners can be used to find and enact optimal reconfigurations in such an evolving context. However, for systems that are highly configurable, such planning becomes intractable due to the size of the adaptation space. To overcome this challenge, in this paper we explore an approach that (a) uses machine learning to find Pareto-optimal configurations without needing to explore every configuration and (b) restricts the search space to such configurations to make planning tractable. We explore this in the context of robot missions that need to consider task timeliness and energy consumption. An independent evaluation shows that our approach results in high-quality adaptation plans in uncertain and adversarial environments.

cs.AI↗

arXiv2015

Synthesis of correct adaptors for protocol enhancement in component-based systems

Adaptation of software components is an important issue in Component Based Software Engineering (CBSE). Building a system from reusable or Commercial-Off-The-Shelf (COTS) components introduces a set of problems, mainly related to compatibility and communication aspects. On one hand, components may have incompatible interaction behavior. This might require to restrict the system's behavior to a subset of safe behaviors. On the other hand, it might be necessary to enhance the current communication protocol. This might require to augment the system's behavior to introduce more sophisticated interactions among components. We address these problems by enhancing our architectural approach which allows for detection and recovery of incompatible interactions by synthesizing a suitable coordinator. Taking into account the specification of the system to be assembled and the specification of the protocol enhancements, our tool (called SYNTHESIS) automatically derives, in a compositional way, the glue code for the set of components. The synthesized glue code implements a software coordinator which avoids incompatible interactions and provides a protocol-enhanced version of the composed system. By using an assume-guarantee technique, we are able to check, in a compositional way, if the protocol enhancement is consistent with respect to the restrictions applied to assure the specified safe behaviors.

cs.SE↗

arXiv2012

Foundations and Tools for End-User Architecting

Within an increasing number of domains an important emerging need is the ability for technically naive users to compose computational elements into novel configurations. Examples include astronomers who create new analysis pipelines to process telescopic data, intelligence analysts who must process diverse sources of unstructured text to discover socio-technical trends, and medical researchers who have to process brain image data in new ways to understand disease pathways. Creating such compositions today typically requires low-level technical expertise, limiting the use of computational methods and increasing the cost of using them. In this paper we describe an approach - which we term end-user architecting - that exploits the similarity between such compositional activities and those of software architects. Drawing on the rich heritage of software architecture languages, methods, and tools, we show how those techniques can be adapted to support end users in composing rich computational systems through domain-specific compositional paradigms and component repositories, without requiring that they have knowledge of the low-level implementation details of the components or the compositional infrastructure. Further, we outline a set of open research challenges that the area of end-user architecting raises.

cs.SE↗