You Can´t Always Get What You Want: Achieving Differentiated Service Levels with Pricing Agents in a Storage Grid

We have designed a new storage grid called Storage@desk to harness unused storage available on desktop machines and turn it into a useful resource for clients. Given the complexity of managing clientspecific QoS requirements, and the dynamism inherent in supply and demand for resources, even a highly experienced system administrator cannot effectively manage resource allocation. In this paper, we present a market-based resource allocation model where pricing agents help resource providers adjust the prices as demand fluctuates. With derivative-following pricing, an agent requires no knowledge of competitors or consumers, which reduces communication overheads and avoids bottlenecks in the system. Individual clients need a variety of service levels and are in competition in scarce resources. Under the budget constraints, the consumers can´t always get what they want. The budgets serve as an incentive for the consumers to react to the price signals. We simulate our model using real world trace data and the results show that, using this model, the system allows the consumers to achieve QoS goals under sufficient budgets and degrade in accordance with relative budget amounts.