What does control theory bring to systems research?

Abstract

Feedback mechanisms can help today's increasingly complex computer systems adapt to changes in workloads or operating conditions. Control theory offers a principled way for designing feedback loops to deal with unpredictable changes, uncertainties, and disturbances in systems. We provide an overview of the joint research at HP Labs and University of Michigan in the past few years, where control theory was applied to automated resource and service level management in data centers. We highlight the key benefits of a control-theoretic approach for systems research, and present specific examples from our experience of designing adaptive resource control systems where this approach worked well. In addition, we outline the main limitations of this approach, and discuss the lessons learned from our experience.