A feedback control mechanism for adaptive SLO maintenance in dynamic service level management

Abstract

With the increasing scale of information technology (IT) service system, traditional threshold-based static service level management (SLM) solution appears to be inadequate to meet current increasingly management requirement of SLM. Due to the stochastic service request rate, the random inherent failure and load surge of IT devices during service operating stage of large scaled IT system, service level objective (SLO) maintenance issue has become a realistic and important issue in dynamic SLM. This paper proposes a closed-loop feedback control mechanism to adaptively maintain SLO that service provider (SP) guaranteed at service operation stage. The mechanism can automatically tune the capacity of IT infrastructure according to service performance dispersion and reduce SLO violations. Considering that the tuning operations also affect service performance, fuzzy control is applied to alleviate the negative effect caused by tuning operations. In the dynamic SLM system that is applied with this mechanism compared with the traditional threshold-based solution, it is proved that the amount of SLO violations obviously decreases, the reliability of the service system increases relatively, and the resource utilization of IT infrastructure is optimized.

Keywords

dynamic service level management (SLM) / service level objective (SLO) maintenance / closed-loop feedback control / fuzzy control