DynaQoS: Model-Free Self-Tuning Fuzzy Control of Virtualized Resources for QoS Provisioning
Cloud elasticity allows dynamic resource provisioning in concert with actual application demands. Feedback control approaches have been applied with success to resource allocation in physical servers. However, cloud dynamics make the design of an accurate and stable resource controller more challenging, especially when response time is considered as the measured output. Response time is highly dependent on the characteristics of workload and sensitive to cloud dynamics. To address the challenges, the authors extend a Self-Tuning Fuzzy Control (STFC) approach, originally developed for response time assurance in web servers to resource allocation in virtualized environments. They introduce mechanisms for adaptive output amplification and flexible rule selection in the STFC approach for better adaptability and stability.