In today's enterprise service oriented software architectures, database systems are a crucial component for the quality of service (QoS) management between customers and service providers. The database workload consists of requests stemming from many different service classes, each of which has a dedicated service level agreement (SLA). We present an adaptive QoS management that is based on an economic model which adaptively penalizes individual requests depending on the SLA and the current

more »

... ee of SLA conformance that the particular service class exhibits. For deriving the adaptive penalty of individual requests, our model differentiates between opportunity costs for underachieving an SLA threshold and marginal gains for (re-)achieving an SLA threshold. Based on the penalties, we develop a database component which schedules requests depending on their deadline and their associated penalty. We report experiments of our operational system to demonstrate the effectiveness of the adaptive QoS management.