¹Electrical and Computer Engineering, Concordia University, Montreal, Canada.
²Ericsson, Montreal, Canada.

---

Abstract—Service providers aim at optimizing system resource utilization while ensuring the quality of service expressed in the Service Level Agreements (SLAs) is met. For this purpose, systems are reconfigured dynamically according to workload variations to satisfy the SLAs while using only the necessary resources. Whenever a dynamic reconfiguration is required because of low resource utilization or potential SLA violations, one or more triggers may be generated. These generated triggers invoke elasticity rules that define actions to be taken in each specific situation. The elasticity rules that are invoked at the same time may lead to actions that may impact each other. As a result, handling each trigger independently may threaten the stability of the system. In this paper, we propose a model-driven framework, which manages the compliance of SLAs and enables dynamic reconfiguration. We use UML models to describe all the artifacts in the framework. All SLA models are transformed into an SLA compliance model which is used at runtime to check SLA compliance and generate triggers when a dynamic reconfiguration is required. In this framework, the actions of the elasticity rules invoked simultaneously are correlated before their application. The proposed correlation is based on the relations between the triggers. We perform a preliminary evaluation of the approach.

Index Terms—Correlation, elasticity rules, dynamic reconfiguration, model driven approach, trigger, SLA violation avoidance.

[PDF]

Cite: Mahin Abbasipour, Ferhat Khendek, Maria Toeroe, "SLA Compliance Checking and System Runtime Reconfiguration — A Model Based Approach," Journal of Software vol. 14, no. 11, pp. 488-528, 2019.