Combinando provisão dinâmica de recursos e rejuvenescimento de software.

Abstract

Dynamic provisioning systems change application capacity in order to use an appropriate number of resources to accommodate current load. These systems benefit applications with time-varying workloads. Rejuvenation systems detect /forecast software failures and restart one or more components of the application in order to bring them to a healthy state. Traditionally, these systems have been developed unaware of one another. We argue that many applications need to be controlled by both systems simultaneously. This is the case, for instance, of Web-based applications. However, we are not aware of research works that study the effects of the coexistence of these systems, actuating over the same application. We identified scenarios in which these systems cannot efficiently actuate over the same application when they are not aware of each other. Component failures cause more damage to the application quality of service in these scenarios than they would cause if they occured in a static over-provisioned infrastructure. Our results show that when both systems coexist independently of each other, application quality of service degrades in comparison with the quality of service provided when each system is acting alone. Simple coordination techniques between dynamic provisioning and rejuvenation actions were proposed. By applying these techniques we can improve the application quality of service.